Devices, systems, and methods for reshaping a heart valve annulus

ABSTRACT

Implants or systems of implants and methods apply a selected force vector or a selected combination of force vectors within or across the left atrium, which allow mitral valve leaflets to better coapt. The implants or systems of implants and methods make possible rapid deployment, facile endovascular delivery, and full intra-atrial retrievability. The implants or systems of implants and methods also make use of strong fluoroscopic landmarks. The implants or systems of implants and methods make use of an adjustable implant and a fixed length implant. The implants or systems of implants and methods may also utilize a bridge stop to secure the implant, and the methods of implantation employ various tools.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/272,716, filed Oct. 13, 2011, now U.S. Pat. No. 8,979,925, issuedMar. 17, 2015, which is a divisional of U.S. patent application Ser. No.12/658,909 filed 17 Feb. 2010, which is a divisional of U.S. applicationSer. No. 11/089,940 filed Mar. 25, 2005, now U.S. Pat. No. 7,691,144,issued Apr. 6, 2010, which is a continuation in-part of U.S. applicationSer. No. 10/894,433, filed Jul. 19, 2004, now U.S. Pat. No. 8,956,407,issued Feb. 17, 2015, and entitled “Devices, Systems, and Methods forReshaping a Heart Valve Annulus”.

FIELD OF THE INVENTION

The invention is directed to devices, systems, and methods for improvingthe function of a heart valve, e.g., in the treatment of mitral valveregurgitation.

BACKGROUND OF THE INVENTION I. The Anatomy of a Healthy Heart

The heart (see FIG. 1) is slightly larger than a clenched fist. It is adouble (left and right side), self-adjusting muscular pump, the parts ofwhich work in unison to propel blood to all parts of the body. The rightside of the heart receives poorly oxygenated (“venous”) blood from thebody from the superior vena cava and inferior vena cava and pumps itthrough the pulmonary artery to the lungs for oxygenation. The left sidereceives well-oxygenation (“arterial”) blood from the lungs through thepulmonary veins and pumps it into the aorta for distribution to thebody.

The heart has four chambers, two on each side—the right and left atria,and the right and left ventricles. The atriums are the blood-receivingchambers, which pump blood into the ventricles. The ventricles are theblood-discharging chambers. A wall composed of fibrous and muscularparts, called the interatrial septum separates the right and leftatriums (see FIGS. 2 to 4). The fibrous interatrial septum is, comparedto the more friable muscle tissue of the heart, a more materially strongtissue structure in its own extent in the heart. An anatomic landmark onthe interatrial septum is an oval, thumbprint sized depression calledthe oval fossa, or fossa ovalis (shown in FIGS. 4 and 6), which is aremnant of the oval foramen and its valve in the fetus. It is free ofany vital structures such as valve structure, blood vessels andconduction pathways. Together with its inherent fibrous structure andsurrounding fibrous ridge which makes it identifiable by angiographictechniques, the fossa ovalis is the favored site for trans-septaldiagnostic and therapeutic procedures from the right into the leftheart. Before birth, oxygenated blood from the placenta was directedthrough the oval foramen into the left atrium, and after birth the ovalforamen closes.

The synchronous pumping actions of the left and right sides of the heartconstitute the cardiac cycle. The cycle begins with a period ofventricular relaxation, called ventricular diastole. The cycle ends witha period of ventricular contraction, called ventricular systole.

The heart has four valves (see FIGS. 2 and 3) that ensure that blooddoes not flow in the wrong direction during the cardiac cycle; that is,to ensure that the blood does not back flow from the ventricles into thecorresponding atria, or back flow from the arteries into thecorresponding ventricles. The valve between the left atrium and the leftventricle is the mitral valve. The valve between the right atrium andthe right ventricle is the tricuspid valve. The pulmonary valve is atthe opening of the pulmonary artery. The aortic valve is at the openingof the aorta.

At the beginning of ventricular diastole (i.e., ventricular filling)(see FIG. 2), the aortic and pulmonary valves are closed to prevent backflow from the arteries into the ventricles. Shortly thereafter, thetricuspid and mitral valves open (as FIG. 2 shows), to allow flow fromthe atriums into the corresponding ventricles. Shortly after ventricularsystole (i.e., ventricular emptying) begins, the tricuspid and mitralvalves close (see FIG. 3)—to prevent back flow from the ventricles intothe corresponding atriums—and the aortic and pulmonary valves open—topermit discharge of blood into the arteries from the correspondingventricles.

The opening and closing of heart valves occur primarily as a result ofpressure differences. For example, the opening and closing of the mitralvalve occurs as a result of the pressure differences between the leftatrium and the left ventricle. During ventricular diastole, whenventricles are relaxed, the venous return of blood from the pulmonaryveins into the left atrium causes the pressure in the atrium to exceedthat in the ventricle. As a result, the mitral valve opens, allowingblood to enter the ventricle. As the ventricle contracts duringventricular systole, the intraventricular pressure rises above thepressure in the atrium and pushes the mitral valve shut.

The mitral and tricuspid valves are defined by fibrous rings ofcollagen, each called an annulus, which forms a part of the fibrousskeleton of the heart. The annulus provides attachments for the twocusps or leaflets of the mitral valve (called the anterior and posteriorcusps) and the three cusps or leaflets of the tricuspid valve. Theleaflets receive chordae tendineae from more than one papillary muscle.In a healthy heart, these muscles and their tendinous chords support themitral and tricuspid valves, allowing the leaflets to resist the highpressure developed during contractions (pumping) of the left and rightventricles. FIGS. 5 and 6 show the chordae tendineae and papillarymuscles in the left ventricle that support the mitral valve.

As FIGS. 2 and 3 show, the anterior (A) portion of the mitral valveannulus is intimate with the non-coronary leaflet of the aortic valve.As FIGS. 2 and 3 also show, the mitral valve annulus is also near othercritical heart structures, such as the circumflex branch of the leftcoronary artery (which supplies the left atrium, a variable amount ofthe left ventricle, and in many people the SA node) and the AV node(which, with the SA node, coordinates the cardiac cycle).

Also in the vicinity of the posterior (P) mitral valve annulus is thecoronary sinus and its tributaries. These vessels drain the areas of theheart supplied by the left coronary artery. The coronary sinus and itstributaries receive approximately 85% of coronary venous blood. Thecoronary sinus empties into the posterior of the right atrium, anteriorand inferior to the fossa ovalis (see FIG. 4). A tributary of thecoronary sinus is called the great cardiac vein, which courses parallelto the majority of the posterior mitral valve annulus, and is superiorto the posterior mitral valve annulus by an average distance of about9.64+/−3.15 millimeters (Yamanouchi, Y, Pacing and ClinicalElectophysiology 21(11):2522-6; 1998).

II. Characteristics and Causes of Mitral Valve Dysfunction

When the left ventricle contracts after filling with blood from the leftatrium, the walls of the ventricle move inward and release some of thetension from the papillary muscle and chords. The blood pushed upagainst the under-surface of the mitral leaflets causes them to risetoward the annulus plane of the mitral valve. As they progress towardthe annulus, the leading edges of the anterior and posterior leafletcome together forming a seal and closing the valve. In the healthyheart, leaflet coaptation occurs near the plane of the mitral annulus.The blood continues to be pressurized in the left ventricle until it isejected into the aorta. Contraction of the papillary muscles issimultaneous with the contraction of the ventricle and serves to keephealthy valve leaflets tightly shut at peak contraction pressuresexerted by the ventricle.

In a healthy heart (see FIGS. 7 and 8), the dimensions of the mitralvalve annulus create an anatomic shape and tension such that theleaflets coapt, forming a tight junction, at peak contraction pressures.Where the leaflets coapt at the opposing medial (CM) and lateral (CL)sides of the annulus are called the leaflet commissures.

Valve malfunction can result from the chordae tendineae (the chords)becoming stretched, and in some cases tearing. When a chord tears, theresult is a leaflet that flails. Also, a normally structured valve maynot function properly because of an enlargement of or shape change inthe valve annulus. This condition is referred to as a dilation of theannulus and generally results from heart muscle failure. In addition,the valve may be defective at birth or because of an acquired disease.

Regardless of the cause (see FIG. 9), mitral valve dysfunction can occurwhen the leaflets do not coapt at peak contraction pressures. As FIG. 9shows, the coaptation line of the two leaflets is not tight atventricular systole. As a result, an undesired back flow of blood fromthe left ventricle into the left atrium can occur.

Mitral regurgitation is a condition where, during contraction of theleft ventricle, the mitral valve allows blood to flow backwards from theleft ventricle into the left atrium. This has two importantconsequences.

First, blood flowing back into the atrium may cause high atrial pressureand reduce the flow of blood into the left atrium from the lungs. Asblood backs up into the pulmonary system, fluid leaks into the lungs andcauses pulmonary edema.

Second, the blood volume going to the atrium reduces volume of bloodgoing forward into the aorta causing low cardiac output. Excess blood inthe atrium over-fills the ventricle during each cardiac cycle and causesvolume overload in the left ventricle.

Mitral regurgitation is measured on a numeric Grade scale of 1+ to 4+ byeither contrast ventriculography or by echocardiographic Dopplerassessment. Grade 1+ is trivial regurgitation and has little clinicalsignificance. Grade 2+ shows a jet of reversed flow going halfway backinto the left atrium. Grade 3 regurgitation shows filling of the leftatrium with reversed flow up to the pulmonary veins and a contrastinjection that clears in three heart beats or less. Grade 4regurgitation has flow reversal into the pulmonary veins and a contrastinjection that does not clear from the atrium in three or fewer heartbeats.

Mitral regurgitation is categorized into two main types, (i) organic orstructural and (ii) functional. Organic mitral regurgitation resultsfrom a structurally abnormal valve component that causes a valve leafletto leak during systole. Functional mitral regurgitation results fromannulus dilation due to primary congestive heart failure, which isitself generally surgically untreatable, and not due to a cause likesevere irreversible ischemia or primary valvular heart disease.

Organic mitral regurgitation is seen when a disruption of the sealoccurs at the free leading edge of the leaflet due to a ruptured chordor papillary muscle making the leaflet flail; or if the leaflet tissueis redundant, the valves may prolapse the level at which coaptationoccurs higher into the atrium with further prolapse opening the valvehigher in the atrium during ventricular systole.

Functional mitral regurgitation occurs as a result of dilation of heartand mitral annulus secondary to heart failure, most often as a result ofcoronary artery disease or idiopathic dilated cardiomyopathy. Comparinga healthy annulus in FIG. 7 to an unhealthy annulus in FIG. 9, theunhealthy annulus is dilated and, in particular, theanterior-to-posterior distance along the minor axis (line P-A) isincreased. As a result, the shape and tension defined by the annulusbecomes less oval (see FIG. 7) and more round (see FIG. 9). Thiscondition is called dilation. When the annulus is dilated, the shape andtension conducive for coaptation at peak contraction pressuresprogressively deteriorate.

The fibrous mitral annulus is attached to the anterior mitral leaflet inone-third of its circumference. The muscular mitral annulus constitutesthe remainder of the mitral annulus and is attached to by the posteriormitral leaflet. The anterior fibrous mitral annulus is intimate with thecentral fibrous body, the two ends of which are called the fibroustrigones. Just posterior to each fibrous trigone is the commissure ofwhich there are two, the anterior medial (CM) and the posterior lateralcommissure (CL). The commissure is where the anterior leaflet meets theposterior leaflet at the annulus.

As before described, the central fibrous body is also intimate with thenon-coronary leaflet of the aortic valve. The central fibrous body isfairly resistant to elongation during the process of mitral annulusdilation. It has been shown that the great majority of mitral annulusdilation occurs in the posterior two-thirds of the annulus known as themuscular annulus. One could deduce thereby that, as the annulus dilates,the percentage that is attached to the anterior mitral leafletdiminishes.

In functional mitral regurgitation, the dilated annulus causes theleaflets to separate at their coaptation points in all phases of thecardiac cycle. Onset of mitral regurgitation may be acute, or gradualand chronic in either organic or in functional mitral regurgitation.

In dilated cardiomyopathy of ischemic or of idiopathic origin, themitral annulus can dilate to the point of causing functional mitralregurgitation. It does so in approximately twenty-five percent ofpatients with congestive heart failure evaluated in the resting state.If subjected to exercise, echocardiography shows the incidence offunctional mitral regurgitation in these patients rises to over fiftypercent.

Functional mitral regurgitation is a significantly aggravating problemfor the dilated heart, as is reflected in the increased mortality ofthese patients compared to otherwise comparable patients withoutfunctional mitral regurgitation. One mechanism by which functionalmitral regurgitation aggravates the situation in these patients isthrough increased volume overload imposed upon the ventricle. Duedirectly to the leak, there is increased work the heart is required toperform in each cardiac cycle to eject blood antegrade through theaortic valve and retrograde through the mitral valve. The latter isreferred to as the regurgitant fraction of left ventricular ejection.This is added to the forward ejection fraction to yield the totalejection fraction. A normal heart has a forward ejection fraction ofabout 50 to 70 percent. With functional mitral regurgitation and dilatedcardiomyopathy, the total ejection fraction is typically less thanthirty percent. If the regurgitant fraction is half the total ejectionfraction in the latter group the forward ejection fraction can be as lowas fifteen percent.

III. Prior Treatment Modalities

In the treatment of mitral valve regurgitation, diuretics and/orvasodilators can be used to help reduce the amount of blood flowing backinto the left atrium. An intra-aortic balloon counterpulsation device isused if the condition is not stabilized with medications. For chronic oracute mitral valve regurgitation, surgery to repair or replace themitral valve is often necessary.

Currently, patient selection criteria for mitral valve surgery are veryselective. Possible patient selection criteria for mitral surgeryinclude: normal ventricular function, general good health, a predictedlifespan of greater than 3 to 5 years, NYHA Class III or IV symptoms,and at least Grade 3 regurgitation. Younger patients with less severesymptoms may be indicated for early surgery if mitral repair isanticipated. The most common surgical mitral repair procedure is fororganic mitral regurgitation due to a ruptured chord on the middlescallop of the posterior leaflet.

In conventional annuloplasty ring repair, the posterior mitral annulusis reduced along its circumference with sutures passed through asurgical annuloplasty sewing ring cuff. The goal of such a repair is tobring the posterior mitral leaflet forward toward to the anteriorleaflet to better allow coaptation.

Surgical edge-to-edge juncture repairs, which can be performedendovascularly, are also made, in which a mid valve leaflet to mid valveleaflet suture or clip is applied to keep these points of the leafletheld together throughout the cardiac cycle. Other efforts have developedan endovascular suture and a clip to grasp and bond the two mitralleaflets in the beating heart.

Grade 3+ or 4+ organic mitral regurgitation may be repaired with suchedge-to-edge technologies. This is because, in organic mitralregurgitation, the problem is not the annulus but in the central valvecomponents.

However, functional mitral regurgitation can persist at a high level,even after edge-to-edge repair, particularly in cases of high Grade 3+and 4+ functional mitral regurgitation. After surgery, the repairedvalve may progress to high rates of functional mitral regurgitation overtime.

In yet another emerging technology, the coronary sinus is mechanicallydeformed through endovascular means applied and contained to functionsolely within the coronary sinus.

It is reported that twenty-five percent of the six million Americans whowill have congestive heart failure will have functional mitralregurgitation to some degree. This constitutes the 1.5 million peoplewith functional mitral regurgitation. Of these, the idiopathic dilatedcardiomyopathy accounts for 600,000 people. Of the remaining 900,000people with ischemic disease, approximately half have functional mitralregurgitation due solely to dilated annulus.

By interrupting the cycle of progressive functional mitralregurgitation, it has been shown in surgical patients that survival isincreased and in fact forward ejection fraction increases in manypatients. The problem with surgical therapy is the significant insult itimposes on these chronically ill patients with high morbidity andmortality rates associated with surgical repair.

The need remains for simple, cost-effective, and less invasive devices,systems, and methods for treating dysfunction of a heart valve, e.g., inthe treatment of organic and functional mitral valve regurgitation.

SUMMARY OF THE INVENTION

The invention comprises devices, systems, and methods for reshaping aheart valve annulus.

One aspect of the invention provides a method of placing an implantwithin a heart chamber. The method can comprise deploying a guide wirein an intravascular path that extends from a first vascular access intoa heart chamber and from the heart chamber to a second vascular accesssite different than the first vascular access site, the guide wirehaving a first end extending beyond the first vascular access site and asecond end extending beyond the second vascular access site, couplingthe implant to one end of the guide wire, and pulling on the other endof the guide wire to pull the implant along at least a portion of theintravascular path into the heart chamber.

The method may include placing the implant in tension within the heartchamber. In one embodiment, the heart chamber can comprise the leftatrium. The implant may comprise, for example, a metallic material orpolymer material or a metallic wire form structure or a polymer wireform structure or suture material or equine pericardium or porcinepericardium or bovine pericardium or preserved mammalian tissue.

An additional aspect of the invention provides a method of implanting abridge element within a left atrium. The method may comprise, forexample, deploying a guide wire in an intravascular path that extendsfrom a first vascular access site through an interatrial septum into theleft atrium and from the left atrium through a great cardiac vein to asecond vascular access site that is different than the first vascularaccess site, the guide wire having a first end extending beyond thefirst vascular access site and a second end extending beyond the secondvascular access site, coupling the bridge element to one end of theguide wire, pulling on the other end of the guide wire to pull theimplant along at least a portion of the intravascular path into the leftatrium, and placing the bridge element in tension between the greatcardiac vein and the interatrial septum. The intravascular path mayextend from the first vascular access site into a right atrium through avena cava, from the right atrium through the interatrial septum into theleft atrium, from the left atrium into and through a great cardiac veininto the right atrium, and from the right atrium through a vena cava tothe second vascular access site. The bridge element may be coupled tothe second end of the guide wire, and then the first end of the guidewire is pulled to pull the bridge element along at least a portion ofthe intravascular path through the great cardiac vein and into the leftatrium.

Another aspect of the invention provides a system comprising an implantsized and configured for placement within a heart chamber, a guide wiresized and configured for deployment in an intravascular path thatextends from a first vascular access into the heart chamber and from theheart chamber to a second vascular access site different than the firstvascular access site, the guide wire having a first end extending beyondthe first vascular access site and a second end extending beyond thesecond vascular access site, and a connector to connect an end of theimplant to one end of the guide wire such that pulling on the other endof the guide wire pulls the implant along at least a portion of theintravascular path into the heart chamber. The bridge element maycomprise, for example, a metallic material or polymer material or ametallic wire form structure or a polymer wire form structure or suturematerial or equine pericardium or porcine pericardium or bovinepericardium or preserved mammalian tissue.

Another aspect of the invention provides a system comprising a bridgeelement sized and configured to be implanted within the left atriumbetween the great cardiac vein and the interatrial septum, the bridgeelement having opposite ends, a guide wire sized and configured to bedeployed in an intravascular path that extends from a first vascularaccess site through an interatrial septum into the left atrium and fromthe left atrium through a great cardiac vein to a second vascular accesssite that is different than the first vascular access site, the guidewire having a first end extending beyond the first vascular access siteand a second end extending beyond the second vascular access site, aconnector to connect an end of the bridge element to one end of theguide wire such that pulling on the other end of the guide wire pullsthe bridge element along at least a portion of the intravascular pathinto the left atrium, a posterior bridge stop sized and configured to besecured to an end of the bridging element to abut against venous tissuewithin the great cardiac vein, and an anterior bridge stop sized andconfigured to be secured to the bridging element to abut against tissueon the interatrial septum within the right atrium.

An additional embodiment provides a method of placing an implant withina heart chamber comprising deploying a guide wire in an intravascularpath that extends from a first vascular access into a heart chamber andfrom the heart chamber to a second vascular access site different thanthe first vascular access site, the guide wire having a first endextending beyond the first vascular access site and a second endextending beyond the second vascular access site, deploying an exchangecatheter in an intravascular path defined by the guide wire, theexchange catheter being deployed over the guide wire and having a firstend extending beyond the first vascular access site and a second endextending beyond the second vascular access site, coupling the implantto one end of the guide wire, and pulling on the other end of the guidewire to pull the implant along at least a portion of the intravascularpath through the exchange catheter and into the heart chamber. Themethod may further include placing the implant in tension within theheart chamber.

Other features and advantages of the invention shall be apparent basedupon the accompanying description, drawings, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an anatomic anterior view of a human heart, with portionsbroken away and in section to view the interior heart chambers andadjacent structures.

FIG. 2 is an anatomic superior view of a section of the human heartshowing the tricuspid valve in the right atrium, the mitral valve in theleft atrium, and the aortic valve in between, with the tricuspid andmitral valves open and the aortic and pulmonary valves closed duringventricular diastole (ventricular filling) of the cardiac cycle.

FIG. 3 is an anatomic superior view of a section of the human heartshown in FIG. 2, with the tricuspid and mitral valves closed and theaortic and pulmonary valves opened during ventricular systole(ventricular emptying) of the cardiac cycle.

FIG. 4 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the interiorof the heart chambers and associated structures, such as the fossaovalis, coronary sinus, and the great cardiac vein.

FIG. 5 is an anatomic lateral view of a human heart with portions brokenaway and in section to show the interior of the left ventricle andassociated muscle and chord structures coupled to the mitral valve.

FIG. 6 is an anatomic lateral view of a human heart with portions brokenaway and in section to show the interior of the left ventricle and leftatrium and associated muscle and chord structures coupled to the mitralvalve.

FIG. 7 is a superior view of a healthy mitral valve, with the leafletsclosed and coapting at peak contraction pressures during ventricularsystole.

FIG. 8 is an anatomic superior view of a section of the human heart,with the normal mitral valve shown in FIG. 7 closed during ventricularsystole (ventricular emptying) of the cardiac cycle.

FIG. 9 is a superior view of a dysfunctional mitral valve, with theleaflets failing to coapt during peak contraction pressures duringventricular systole, leading to mitral regurgitation.

FIGS. 10A and 10B are anatomic anterior perspective views of the leftand right atriums, with portions broken away and in section to show thepresence of an implant system that includes an inter-atrial bridgingelement that spans the mitral valve annulus, with a posterior bridgestop positioned in the great cardiac vein and an anterior bridge stop,including a septal member, positioned on the inter-atrial septum, theinter-atrial bridging element extending in an essentially straight pathgenerally from a mid-region of the annulus to the inter-atrial septum.

FIG. 10C is an anatomic anterior perspective view of an alternativeembodiment of the implant system shown in FIGS. 10A and 10B, showing ananterior bridge stop without the addition of a septal member.

FIG. 11A is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system of the type shown in FIGS. 10A and 10B, with theanterior region of the implant extending through a pass-throughstructure, such as a septal member, in the inter-atrial septum andsituated in the superior vena cava.

FIG. 11B is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system of the type shown in FIGS. 10A and 10B, with theanterior region of the implant extending through a pass-throughstructure, such as a septal member, in the inter-atrial septum andsituated in the inferior vena cava.

FIG. 11C is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system of the type shown in FIGS. 10A to 10C, with theanterior region of the implant situated on the inter-atrial septum, aswell as in the superior vena cava and the inferior vena cava.

FIG. 12 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in an essentiallystraight path generally from a lateral region of the annulus.

FIG. 13 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in an upwardlycurved or domed path generally from a lateral region of the annulus.

FIG. 14 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in a downwardlycurved path generally from a lateral region of the annulus.

FIG. 15 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in a curvilinearpath, bending around a trigone of the annulus generally from amid-region region of the annulus.

FIG. 16 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in a curvilinearpath, bending around a trigone of the annulus generally from amid-region region of the annulus, as well as elevating in an arch towardthe dome of the left atrium.

FIG. 17 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in a curvilinearpath, bending around a trigone of the annulus generally from amid-region region of the annulus, as well as dipping downward toward theplane of the valve.

FIG. 18 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes two inter-atrial bridging elementsthat span the mitral valve annulus, each with a posterior bridge stop inthe great cardiac vein and an anterior bridge stop on the inter-atrialseptum, the inter-atrial bridging elements both extending in generallystraight paths from different regions of the annulus.

FIG. 19 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes two inter-atrial bridging elementsthat span the mitral valve annulus, each with a posterior regionsituated in the great cardiac vein and an anterior region situated onthe interatrial septum, the inter-atrial bridging elements bothextending in generally curvilinear paths from adjacent regions of theannulus.

FIG. 20 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes three inter-atrial bridging elementsthat span the mitral valve annulus, each with a posterior regionsituated in the great cardiac vein and an anterior region situated onthe interatrial septum, two of the inter-atrial bridging elementsextending in generally straight paths from different regions of theannulus, and the third inter-atrial bridging elements extending in agenerally curvilinear path toward a trigone of the annulus.

FIG. 21A is a side view of a septal member which may be used as part ofthe implant system of the type shown in FIGS. 10A and 10B.

FIG. 21B is a side view of a deployed septal member of the type shown inFIG. 21A, showing the member sandwiching portions of the septum throughan existing hole.

FIGS. 22A and 22B are sectional views showing the ability of a bridgestop used in conjunction with the implant shown in FIGS. 10A to 10C tomove back and forth independent of the septal wall and inner wall of thegreat cardiac vein.

FIGS. 23 to 30 are anatomic views depicting representativecatheter-based devices and steps for implanting an implant system of thetype shown in FIGS. 10A to 10C.

FIG. 31 is an anatomic section view of the left atrium and associatedmitral valve structure, showing mitral dysfunction.

FIG. 32 is an anatomic superior view of a section of the human heart,showing the presence of an implant system of the type shown in FIGS. 10Aand 10B.

FIG. 33 is an anatomic section view of the implant system takengenerally along line 33-33 in FIG. 32, showing the presence of animplant system of the type shown in FIGS. 10A and 10B, and showingproper coaptation of the mitral valve leaflets.

FIGS. 34A to 34D are sectional views of a crimp tube for connecting aguide wire to a bridging element, and showing the variations in thecrimps used.

FIG. 35A is an anatomic partial view of a patient depicting accesspoints used for implantation of an implant system, and also showing aloop guide wire accessible to the exterior the body at two locations.

FIG. 35B is an anatomic view depicting a representative alternativecatheter-based device for implanting an implant system of the type shownin FIGS. 10A to 10C, and showing a bridging element being pulled throughthe vasculature structure by a loop guide wire.

FIG. 36A is an anatomic partial view of a patient showing a bridge stopconnected to a bridging element in preparation to be pulled and/orpushed through the vasculature structure and positioned within the greatcardiac vein.

FIG. 36B is an anatomic view depicting a representative alternativecatheter-based device for implanting a system of the type shown in FIGS.10A to 10C, and showing a bridge stop being positioned within the greatcardiac vein.

FIG. 37A is a perspective view of a catheter used in the implantation ofan implant system of the type shown in FIGS. 10A to 10C.

FIG. 37B is a partial sectional view showing a magnetic head of thecatheter as shown in FIG. 37A.

FIG. 38 is a perspective view of an additional catheter which may beused in the implantation of an implant system of the type shown in FIGS.10A to 10C.

FIG. 39 is a partial perspective view of the interaction between themagnetic head of the catheter shown in FIG. 37A and the magnetic head ofthe catheter shown in FIG. 38, showing a guide wire extending out of onemagnetic head and into the other magnetic head.

FIG. 40 is an anatomic partial perspective view of the magnetic catheterheads shown in FIG. 39, with one catheter shown in the left atrium andone catheter shown in the great cardiac vein.

FIG. 41 is a perspective view of an additional catheter which may beused in the implantation of an implant system of the type shown in FIGS.10A to 10C.

FIGS. 42A to 42C are partial perspective views of catheter tips whichmay be used with the catheter shown in FIG. 41.

FIG. 43A is a perspective view of a symmetrically shaped T-shaped bridgestop or member which may be used with the implant system of the typeshown in FIGS. 10A to 10C.

FIG. 43B is a perspective view of an alternative embodiment of theT-shaped bridge stop shown in FIG. 43A, showing the bridge stop beingasymmetric and having one limb shorter than the other.

FIG. 44A is an exploded view of a bridge stop and associated driverwhich may be used with the implant system of the type shown in FIGS. 10Ato 10C.

FIG. 44B is a bottom view of the bridge stop shown in FIG. 44A.

FIG. 44C is a top view of a screw used in the bridge stop of the typeshown in FIG. 44A.

FIG. 45A is an anatomic partial perspective view of alternative magneticcatheter heads, with one catheter shown in the left atrium and onecatheter shown in the great cardiac vein, and showing a side to endconfiguration.

FIG. 45B is a partial sectional view of the alternative magneticcatheter heads of the type shown in FIG. 45A, showing a guide wirepiercing the wall of the great cardiac vein and left atrium andextending into the receiving catheter.

FIG. 45C is a partial perspective view of an alternative magnetic headof the type shown in FIG. 45B.

FIG. 46 is an anatomic partial perspective view of an additionalalternative embodiment for the magnetic catheter heads of the type shownin FIG. 45A, showing a side to side configuration.

FIGS. 47A to 51 are perspective and sectional views of alternativeembodiments of a bridge stop of the type shown in FIG. 44A.

FIG. 52A is a perspective view of an alternative embodiment of aT-shaped bridge stop or member of the type shown in FIG. 43A, showing aballoon expandable or self-expanding stent with a reinforcing strut.

FIG. 52B is a perspective view of an alternative embodiment of aT-shaped bridge stop or member of the type shown in FIG. 52A, showingthe expandable or self-expanding stent in a lattice or half stentconfiguration.

FIGS. 53A to 53F are perspective views showing alternative methods ofconnecting a bridging element to a bridge stop or T-shaped member.

FIGS. 54 to 56A are perspective views of alternative implant systems ofthe type shown in FIGS. 10A to 10C, showing alternative bridge locks inboth the anterior bridge stop region and the posterior bridge stopregion.

FIG. 56B is a side view of an alternative bridge stop of the type shownin FIG. 56A.

FIGS. 57 to 59 are perspective views of additional alternative bridgelocks.

FIG. 60A is a perspective view of an alternative bridge stop and showingthe deployment catheter and deployment wire.

FIG. 60B is a side view of the alternative bridge stop of the type shownin FIG. 60A, showing the bridge stop in the deployment catheter prior tobeing deployed.

FIG. 61A is a perspective view of an alternative bridge stop including asingle layer of pericardium.

FIG. 61B is a side view of the alternative bridge stop of the type shownin FIG. 61A, showing the bridge stop in the deployment catheter prior tobeing deployed.

FIG. 62A is a perspective view of an alternative bridge stop includingmultiple layers of pericardium.

FIG. 62B is a side view of the alternative bridge stop of the type shownin FIG. 62A, showing the bridge stop in the deployment catheter prior tobeing deployed.

FIG. 63A is a perspective view of an alternative bridge stop including aballoon structure.

FIG. 63B is a side view of the alternative bridge stop of the type shownin FIG. 63A, showing the bridge stop in the deployment catheter prior tobeing deployed.

FIG. 63C is a side view of the alternative bridge stop of the type shownin FIG. 63A, showing the bridge stop just after exiting the deploymentcatheter and prior to being deployed.

FIG. 64 is an anatomic anterior perspective view of the left atrium anda portion of the right atrium, with portions broken away and in sectionto show the presence of an alternative implant system of the type shownin FIGS. 10A to 10C, the alternative implant system includes a fixedlength inter-atrial bridging element that spans the mitral valveannulus, with a posterior bridge stop positioned in the great cardiacvein and an anterior bridge stop positioned on the inter-atrial septum,the inter-atrial bridging element extending in an essentially straightpath generally from a mid-region of the annulus to the inter-atrialseptum.

FIG. 65 is an anatomic anterior perspective view of the left atrium, anda portion of the right atrium, with portions broken away and in sectionto show the presence of an alternative implant system of the type shownin FIG. 64, the alternative implant system includes a fixed lengthinter-atrial bridging element that spans the mitral valve annulus, witha posterior region situated in the great cardiac vein and an anteriorregion situated on the interatrial septum, the fixed length inter-atrialbridging element extending in a curvilinear path, bending around atrigone of the annulus generally from a mid-region region of theannulus, as well as dipping downward toward the plane of the valve.

FIG. 66 is an anatomic anterior perspective view of the left atrium, anda portion of the right atrium, with portions broken away and in sectionto show the presence of an alternative implant system of the type shownin FIG. 64, the alternative implant system includes a fixed lengthinter-atrial bridging element that spans the mitral valve annulus, witha posterior region situated in the great cardiac vein and an anteriorregion situated on the interatrial septum, the fixed length inter-atrialbridging element extending in a curvilinear path, bending around atrigone of the annulus generally from a mid-region region of theannulus, as well as elevating in an arch toward the dome of the leftatrium.

FIG. 67 is a side view of a fixed length inter-atrial bridging elementof the type shown in FIG. 64, and showing the fixed length bridgingelement with a connective head on a first end and a stop on a secondend.

FIG. 68 is a side view of an arched or non-linear fixed lengthinter-atrial bridging element of the type shown in FIGS. 65 and 66, andshowing the arched fixed length bridging element with a connective headon a first end and a stop on a second end.

FIG. 69 is a perspective view of the arched fixed length inter-atrialbridging element of the type shown in FIG. 68, and showing and showingan alternative embodiment for a bridge stop on a second end.

FIGS. 70A and 70B are perspective views showing the connective head ofthe fixed length bridging element guided by the tracking rail into thereceiving aperture in a posterior or anterior bridge stop structure.

FIGS. 71A and 71B are sectional views showing the ability of a bridgestop used in conjunction with the implant shown in FIG. 64 to move backand forth independent of the septal wall and inner wall of the greatcardiac vein.

FIG. 72 is an anatomic anterior perspective view of the left atrium anda portion of the right atrium, with portions broken away and in sectionto show a step of implanting the implant system including the fixedlength inter-atrial bridging element of the type shown in FIG. 64.

FIG. 73 is an anatomic anterior perspective view of the left atrium anda portion of the right atrium, with portions broken away and in sectionto show a step of implanting the implant system including the archedfixed length inter-atrial bridging element of the type shown in FIGS. 65and 66.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Although the disclosure hereof is detailed and exact to enable thoseskilled in the art to practice the invention, the physical embodimentsherein disclosed merely exemplify the invention which may be embodied inother specific structures. While the preferred embodiment has beendescribed, the details may be changed without departing from theinvention, which is defined by the claims.

I. Trans-Septal Implants for Direct Shortening of the Minor Axis of aHeart Valve Annulus

A. Implant Structure

FIGS. 10A to 10C show embodiments of an implant 10 that is sized andconfigured to extend across the left atrium in generally ananterior-to-posterior direction, spanning the mitral valve annulus. Theimplant 10 comprises a spanning region or bridging element 12 having aposterior bridge stop region 14 and an anterior bridge stop region 16.

The posterior bridge stop region 14 is sized and configured to allow thebridging element 12 to be placed in a region of atrial tissue above theposterior mitral valve annulus. This region is preferred, because itgenerally presents more tissue mass for obtaining purchase of theposterior bridge stop region 14 than in a tissue region at or adjacentto the posterior mitral annulus. Engagement of tissue at thissupra-annular location also may reduce risk of injury to the circumflexcoronary artery. In a small percentage of cases, the circumflex coronaryartery may pass over and medial to the great cardiac vein on the leftatrial aspect of the great cardiac vein, coming to lie between the greatcardiac vein and endocardium of the left atrium. However, since theforces in the posterior bridge stop region are directed upward andinward relative to the left atrium and not in a constricting manneralong the long axis of the great cardiac vein, the likelihood ofcircumflex artery compression is less compared to other technologies inthis field that do constrict the tissue of the great cardiac vein.Nevertheless, should a coronary angiography reveal circumflex arterystenosis, the symmetrically shaped posterior bridge stop may be replacedby an asymmetrically shaped bridge stop, such as where one limb of aT-shaped member is shorter than the other, thus avoiding compression ofthe crossing point of the circumflex artery. The asymmetric form mayalso be selected first based on a pre-placement angiogram.

An asymmetric posterior bridge stop may be utilized for other reasons aswell. The asymmetric posterior bridge stop may be selected where apatient is found to have a severely stenotic distal great cardiac vein,where the asymmetric bridge stop better serves to avoid obstruction ofthat vessel. In addition, an asymmetric bridge stop may be chosen forits use in selecting application of forces differentially andpreferentially on different points along the posterior mitral annulus tooptimize treatment, i.e., in cases of malformed or asymmetrical mitralvalves.

The anterior bridge stop region 16 is sized and configured to allow thebridging element 12 to be placed, upon passing into the right atriumthrough the septum, adjacent tissue in or near the right atrium. Forexample, as is shown in FIGS. 10A to 10C, the anterior bridge stopregion 16 may be adjacent or abutting a region of fibrous tissue in theinteratrial septum. As shown, the bridge stop site 16 is desirablysuperior to the anterior mitral annulus at about the same elevation orhigher than the elevation of the posterior bridge stop region 14. In theillustrated embodiment, the anterior bridge stop region 16 is adjacentto or near the inferior rim of the fossa ovalis. Alternatively, theanterior bridge stop region 16 can be located at a more superiorposition in the septum, e.g., at or near the superior rim of the fossaovalis. The anterior bridge stop region 16 can also be located in a moresuperior or inferior position in the septum, away from the fossa ovalis,provided that the bridge stop site does not harm the tissue region.

Alternatively, as can be seen in FIGS. 11A and 11B, the anterior bridgestop region 16, upon passing through the septum into the right atrium,may be positioned within or otherwise situated in the superior vena cava(SVC) or the inferior vena cava (IVC), instead of at the septum itself.

In use, the spanning region or bridging element 12 can be placed intotension between the two bridge stop regions 14 and 16. The implant 10thereby serves to apply a direct mechanical force generally in aposterior to anterior direction across the left atrium. The directmechanical force can serve to shorten the minor axis (line P-A in FIG.7) of the annulus. In doing so, the implant 10 can also reactivelyreshape the annulus along its major axis (line CM-CL in FIG. 7) and/orreactively reshape other surrounding anatomic structures. It should beappreciated, however, the presence of the implant 10 can serve tostabilize tissue adjacent the heart valve annulus, without affecting thelength of the minor or major axes.

It should also be appreciated that, when situated in other valvestructures, the axes affected may not be the “major” and “minor” axes,due to the surrounding anatomy. In addition, in order to be therapeutic,the implant 10 may only need to reshape the annulus during a portion ofthe heart cycle, such as during late diastole and early systole when theheart is most full of blood at the onset of ventricular systoliccontraction, when most of the mitral valve leakage occurs. For example,the implant 10 may be sized to restrict outward displacement of theannulus during late ventricular diastolic relaxation as the annulusdilates.

The mechanical force applied by the implant 10 across the left atriumcan restore to the heart valve annulus and leaflets a more normalanatomic shape and tension. The more normal anatomic shape and tensionare conducive to coaptation of the leaflets during late ventriculardiastole and early ventricular systole, which, in turn, reduces mitralregurgitation.

In its most basic form, the implant 10 is made from a biocompatiblemetallic or polymer material, or a metallic or polymer material that issuitably coated, impregnated, or otherwise treated with a material toimpart biocompatibility, or a combination of such materials. Thematerial is also desirably radio-opaque or incorporates radio-opaquefeatures to facilitate fluoroscopic visualization.

The implant 10 can be formed by bending, shaping, joining, machining,molding, or extrusion of a metallic or polymer wire form structure,which can have flexible or rigid, or inelastic or elastic mechanicalproperties, or combinations thereof. Alternatively, the implant 10 canbe formed from metallic or polymer thread-like or suture material.Materials from which the implant 10 can be formed include, but are notlimited to, stainless steel, Nitinol, titanium, silicone, plated metals,Elgiloyl™, NP55, and NP57.

The implant 10 can take various shapes and have various cross-sectionalgeometries. The implant 10 can have, e.g., a generally curvilinear(i.e., round or oval) cross-section, or a generally rectilinear crosssection (i.e., square or rectangular), or combinations thereof. Shapesthat promote laminar flow and therefore reduce hemolysis arecontemplated, with features such as smoother surfaces and longer andnarrower leading and trailing edges in the direction of blood flow.

B. The Posterior Bridge Stop Region

The posterior bridge stop region 14 is sized and configured to belocated within or at the left atrium at a supra-annular position, i.e.,positioned within or near the left atrium wall above the posteriormitral annulus.

In the illustrated embodiment, the posterior bridge stop region 14 isshown to be located generally at the level of the great cardiac vein,which travels adjacent to and parallel to the majority of the posteriormitral valve annulus. This tributary of the coronary sinus can provide astrong and reliable fluoroscopic landmark when a radio-opaque device isplaced within it or contrast dye is injected into it. As previouslydescribed, securing the bridging element 12 at this supra-annularlocation also lessens the risk of encroachment of and risk of injury tothe circumflex coronary artery compared to procedures applied to themitral annulus directly. Furthermore, the supra-annular position assuresno contact with the valve leaflets therefore allowing for coaptation andreduces the risk of mechanical damage.

The great cardiac vein also provides a site where relatively thin,non-fibrous atrial tissue can be readily augmented and consolidated. Toenhance hold or purchase of the posterior bridge stop region 14 in whatis essentially non-fibrous heart tissue, and to improve distribution ofthe forces applied by the implant 10, the posterior bridge stop region14 may include a posterior bridge stop 18 placed within the greatcardiac vein and abutting venous tissue. This makes possible thesecuring of the posterior bridge stop region 14 in a non-fibrous portionof the heart in a manner that can nevertheless sustain appreciable holdor purchase on that tissue for a substantial period of time, withoutdehiscence, expressed in a clinically relevant timeframe.

C. The Anterior Bridge Stop Region

The anterior bridge stop region 16 is sized and configured to allow thebridging element 12 to remain firmly in position adjacent or near thefibrous tissue and the surrounding tissues in the right atrium side ofthe atrial septum. The fibrous tissue in this region provides superiormechanical strength and integrity compared with muscle and can betterresist a device pulling through. The septum is the most fibrous tissuestructure in its own extent in the heart. Surgically handled, it isusually one of the only heart tissues into which sutures actually can beplaced and can be expected to hold without pledgets or deep grasps intomuscle tissue, where the latter are required.

As FIGS. 10A to 10C show, the anterior bridge stop region 16 passesthrough the septal wall at a supra-annular location above the plane ofthe anterior mitral valve annulus. The supra-annular distance on theanterior side can be generally at or above the supra-annular distance onthe posterior side. As before pointed out, the anterior bridge stopregion 16 is shown in FIGS. 10A to 10C at or near the inferior rim ofthe fossa ovalis, although other more inferior or more superior sitescan be used within or outside the fossa ovalis, taking into account theneed to prevent harm to the septal tissue and surrounding structures.

By locating the bridging element 12 at this supra-annular level withinthe right atrium, which is fully outside the left atrium and spaced wellabove the anterior mitral annulus, the implant 10 avoids theimpracticalities of endovascular attachment at or adjacent to theanterior mitral annulus, where there is just a very thin rim of annulustissue that is bounded anteriorly by the anterior leaflet, inferiorly bythe aortic outflow tract, and medially by the atrioventricular node ofthe conduction system. The anterior mitral annulus is where thenon-coronary leaflet of the aortic valve attaches to the mitral annulusthrough the central fibrous body. Anterior location of the implant 10 inthe supra-annular level within the right atrium (either in the septum orin a vena cava) avoids encroachment of and risk of injury to both theaortic valve and the AV node.

The purchase of the anterior bridge stop region 16 in fibrous septaltissue is desirably enhanced by a septal member 30 or an anterior bridgestop 20, or a combination of both. FIGS. 10A and 10B show the anteriorbridge stop region including a septal member 30. FIG. 10C shows theanterior bridge stop region without a septal member. The septal member30 may be an expandable device and also may be a commercially availabledevice such as a septal occluder, e.g., Amplatzer® PFO Occluder (seeFIGS. 21A and 21B). The septal member 30 preferably mechanicallyamplifies the hold or purchase of the anterior bridge stop region 16 inthe fibrous tissue site. The septal member 30 also desirably increasesreliance, at least partly, on neighboring anatomic structures of theseptum to make firm the position of the implant 10. In addition, theseptal member 30 may also serve to plug or occlude the small aperturethat was created in the fossa ovalis or surrounding area during theimplantation procedure.

Anticipating that pinpoint pulling forces will be applied by theanterior bridge stop region 16 to the septum, the forces acting on theseptal member 30 should be spread over a moderate area, without causingimpingement on valve, vessels or conduction tissues. With the pulling ortensioning forces being transmitted down to the annulus, shortening ofthe minor axis is achieved. A flexurally stiff septal member ispreferred because it will tend to cause less focal narrowing in thedirection of bridge element tension of the left atrium as tension on thebridging element is increased. The septal member 30 should also have alow profile configuration and highly washable surfaces to diminishthrombus formation for devices deployed inside the heart. The septalmember may also have a collapsed configuration and a deployedconfiguration. The septal member 30 may also include a hub 31 (see FIGS.21A and 21B) to allow attachment of the bridge stop 20. A septal bracemay also be used in combination with the septal member 30 and anteriorbridge stop 20 to distribute forces uniformly along the septum (see FIG.11C). Alternatively, devices in the IVC or the SVC can be used as bridgestop sites (see FIGS. 11A and 11B), instead of confined to the septum.

Location of the posterior and anterior bridge stop regions 14 and 16having radio-opaque bridge locks and well demarcated fluoroscopiclandmarks respectively at the supra-annular tissue sites just described,not only provides freedom from key vital structure damage or localimpingement—e.g., to the circumflex artery, AV node, and the leftcoronary and non-coronary cusps of the aortic valve—but thesupra-annular focused sites are also not reliant on purchase betweentissue and direct tension-loaded penetrating/biting/holding tissueattachment mechanisms. Instead, physical structures and forcedistribution mechanisms such as stents, T-shaped members, and septalmembers can be used, which better accommodate the attachment or abutmentof mechanical levers and bridge locks, and through which potentialtissue tearing forces can be better distributed. Further, the bridgestop sites 14, 16 do not require the operator to use complex imaging.Adjustment of implant position after or during implantation is alsofacilitated, free of these constraints. The bridge stop sites 14, 16also make possible full intra-atrial retrieval of the implant 10 byendovascularly snaring and then cutting the bridging element 12 ateither side of the left atrial wall, from which it emerges.

D. Orientation of the Bridging Element

In the embodiments shown in FIGS. 10A to 10C, the implant 10 is shown tospan the left atrium beginning at a posterior point of focus superior tothe approximate mid-point of the mitral valve annulus, and proceeding inan anterior direction in a generally straight path directly to theregion of anterior focus in the septum. As shown in FIGS. 10A to 10C,the spanning region or bridging element 12 of the implant 10 may bepreformed or otherwise configured to extend in this essentially straightpath above the plane of the valve, without significant deviation inelevation toward or away from the plane of the annulus, other than asdictated by any difference in elevation between the posterior andanterior regions of placement.

Lateral or medial deviations and/or superior or inferior deviations inthis path can be imparted, if desired, to affect the nature anddirection of the force vector or vectors that the implant 10 applies. Itshould be appreciated that the spanning region or bridging element 12can be preformed or otherwise configured with various medial/lateraland/or inferior/superior deviations to achieve targeted annulus and/oratrial structure remodeling, which takes into account the particulartherapeutic needs and morphology of the patient. In addition, deviationsin the path of the bridging element may also be imparted in order toavoid the high velocity blood path within a heart chamber, such as theleft atrium.

For example, as shown in FIG. 12, the implant 10 is shown to span theleft atrium beginning at a posterior region that is closer to a lateraltrigone of the annulus (i.e., farther from the septum). Alternatively,the posterior region can be at a position that is closer to a medialtrigone of the annulus (i.e., closer to the septum). From either one ofthese posterior regions, the implant 10 can extend in an anteriordirection in a straight path directly to the anterior region in theseptum. As shown in FIG. 12, like FIG. 10A, the spanning region orbridging element 12 of the implant 10 is preformed or otherwiseconfigured to extend in an essentially straight path above the plane ofthe valve, without significant deviation in elevation toward or awayfrom the plane of the annulus, other than as dictated by the differencein elevation, if any, between the posterior and anterior regions.

Regardless of the particular location of the posterior region (see FIG.13), the spanning region or bridging element 12 of the implant 10 can bepreformed or otherwise configured to arch upward above the plane of thevalve toward the dome of the left atrium Alternatively (see FIG. 14),the spanning region or bridging element 12 of the implant 10 can bepreformed or otherwise configured to dip downward toward the plane ofthe valve toward the annulus, extending close to the plane of the valve,but otherwise avoiding interference with the valve leaflets. Or, stillalternatively (see FIG. 15), the spanning region or bridging element 12of the implant 10 can be preformed or otherwise configured to follow acurvilinear path, bending towards a trigone (medial or lateral) of theannulus before passage to the anterior region.

Various combinations of lateral/medial deviations and superior/inferiordeviations of the spanning region or bridging element 12 of the implant10 are of course possible. For example, as shown in FIG. 16, thespanning region or bridging element 12 can follow a curvilinear pathbending around a trigone (medial or lateral) of the annulus as well aselevate in an arch away from the plane of the valve. Or, as shown inFIG. 17, the spanning region or bridging element 12 can follow acurvilinear path bending around a trigone (medial or lateral) of theannulus as well as dip toward the plane of the valve.

Regardless of the orientation, more than one implant 10 can be installedto form an implant system 22. For example, FIG. 18 shows a system 22comprising a lateral implant 10L and a medial implant 10M of a typeconsistent with the implant 10 as described. FIG. 18 shows the implants10L and 10M being located at a common anterior bridge stop region 16. Itshould be appreciated that the implants 10L and 10M can also includespaced apart anterior bridge stop regions.

One or both of the implants 10L and 10M can be straight (as in FIG. 12),or arch upward (as in FIG. 13), or bend downward (as in FIG. 14). Agiven system 10 can comprise lateral and medial implants 10L and 10M ofdifferent configurations. Also, a given system 22 can comprise more thantwo implants 10.

FIG. 19 shows a system 22 comprising two curvilinear implants 10L and10M of the type shown in FIG. 15. In FIG. 19, the curvilinear implants10L and 10M are shown to be situated at a common posterior region, butthe implants 10 can proceed from spaced apart posterior regions, aswell. One or both of the curvilinear implants 10L and 10M can beparallel with respect to the plane of the valve (as in FIG. 15), or archupward (as in FIG. 16), or bend downward (as in FIG. 17). A given system22 can comprise curvilinear implants 10L and 10M of differentconfigurations.

FIG. 20 shows a system 22 comprising a direct middle implant 10D, amedial curvilinear implant 10M, and a direct lateral implant 10L. One,two, or all of the implants 10 can be parallel to the valve, or archupward, or bend downward, as previously described.

E. Posterior and Anterior Bridge Stop

It is to be appreciated that a bridge stop as described herein,including a posterior or anterior bridge stop, describes an apparatusthat may releasibly hold the bridging element 12 in a tensioned state.As can be seen in FIGS. 22A and 22B, bridge stops 20 and 18 respectivelyare shown releasibly secured to the bridging element 12, allowing thebridge stop structure to move back and forth independent of theinter-atrial septum and inner wall of the great cardiac vein during aportion of the cardiac cycle when the tension force may be reduced orbecomes zero. Alternative embodiments are also described, all of whichmay provide this function. It is also to be appreciated that the generaldescriptions of posterior and anterior are non-limiting to the bridgestop function, i.e., a posterior bridge stop may be used anterior, andan anterior bridge stop may be used posterior.

When the bridge stop is in an abutting relationship to a septal memberor a T-shaped member, for example, the bridge stop allows the bridgingelement to move freely within or around the septal member or T-shapedmember, i.e., the bridging element is not connected to the septal memberor T-shaped member. In this configuration, the bridging element is heldin tension by the bridge stop, whereby the septal member or T-shapedmember serves to distribute the force applied by the bridging elementacross a larger surface area. Alternatively, the bridge stop may bemechanically connected to the septal member or T-shaped member, e.g.,when the bridge stop is positioned over and secured to the septal memberhub. In this configuration, the bridging element is fixed relative tothe septal member position and is not free to move about the septalmember.

II. General Methods of Trans-Septal Implantation

The implants 10 or implant systems 22 as just described lend themselvesto implantation in a heart valve annulus in various ways. The implants10 or implant systems 22 can be implanted, e.g., in an open heartsurgical procedure. Alternatively, the implants 10 or implant systems 22can be implanted using catheter-based technology via a peripheral venousaccess site, such as in the femoral or jugular vein (via the IVC or SVC)under image guidance, or trans-arterial retrograde approaches to theleft atrium through the aorta from the femoral artery also under imageguidance.

Alternatively, the implants 10 or implant systems 22 can be implantedusing thoracoscopic means through the chest, or by means of othersurgical access through the right atrium, also under image guidance.Image guidance includes but is not limited to fluoroscopy, ultrasound,magnetic resonance, computed tomography, or combinations thereof.

The implants 10 or implant systems 22 may comprise independentcomponents that are assembled within the body to form an implant, oralternatively, independent components that are assembled exterior thebody and implanted as a whole.

FIGS. 23 to 30 show a representative embodiment of the deployment of animplant 10 of the type shown in FIGS. 10A to 10C by a percutaneous,catheter-based procedure, under image guidance.

Percutaneous vascular access is achieved by conventional methods intothe femoral or jugular vein, or a combination of both. As FIGS. 23 and24 show, under image guidance, a first catheter, or great cardiac veincatheter 40, and a second catheter, or left atrium catheter 60, aresteered through the vasculature into the right atrium. It is a functionof the great cardiac vein (GCV) catheter 40 and left atrium (LA)catheter 60 to establish the posterior bridge end stop region. Catheteraccess to the right and left atriums can be achieved through either afemoral vein to IVC or SVC route (in the latter case, for a caval brace)or an upper extremity or neck vein to SVC or IVC route (in the lattercase, for a caval brace). In the case of the SVC, the easiest access isfrom the upper extremity or neck venous system; however, the IVC canalso be accessed by passing through the SVC and right atrium. Similarlythe easiest access to the IVC is through the femoral vein; however theSVC can also be accessed by passing through the IVC and right atrium.FIGS. 23, 24, 27, 28 and 29 show access through both a SVC route and anIVC route for purposes of illustration.

The implantation of the implant 10 or implant systems 22 are firstdescribed here in four general steps. Each of these steps, and thevarious tools used, is then described with additional detail below insection III. Additionally, alternative implantation steps may be usedand are described in section IV. Additional alternative embodiments of abridge stop are described in section V, additional alternativeembodiments of a T-shaped member or bridge stop are described in sectionVI, and additional alternative embodiments of an anterior bridge stopare described in section VII.

A first implantation step can be generally described as establishing theposterior bridge stop region 14. As can be seen in FIG. 24, the GCVcatheter 40 is steered through the vasculature into the right atrium.The GCV catheter 40 is then steered through the coronary sinus and intothe great cardiac vein. The second catheter, or LA catheter 60, is alsosteered through the vasculature and into the right atrium. The LAcatheter 60 then passes through the septal wall at or near the fossaovalis and enters the left atrium. A Mullins™ catheter 26 may beprovided to assist the guidance of the LA catheter 60 into the leftatrium. Once the GCV catheter 40 and the LA catheter 60 are in theirrespective positions in the great cardiac vein and left atrium, it is afunction of the GCV and LA catheters 40, 60 to configure the posteriorbridge stop region 14.

A second step can be generally described as establishing thetrans-septal bridging element 12. A deployment catheter 24 via the LAcatheter 60 is used to position a posterior bridge stop 18 and apreferably preattached and predetermined length of bridging element 12within the great cardiac vein (see FIG. 27). The predetermined length ofbridging element 12, e.g., two meters, extends from the posterior bridgestop 18, through the left atrium, through the fossa ovalis, through thevasculature, and preferably remains accessible exterior the body. Thepredetermined length of bridging element may be cut or detached in afuture step, leaving implanted the portion extending from the posteriorbridge stop 18 to the anterior bridge stop 20. Alternatively, thebridging element 20 may not be cut or detached at the anterior bridgestop 20, but instead the bridging element 20 may be allowed to extendinto the IVC for possible future retrieval.

A third step can be generally described as establishing the anteriorbridge stop region 16 (see FIG. 29). The bridging element 12 is firstthreaded through the septal member 30. The septal member 30 is thenadvanced over the bridging element 12 in a collapsed condition throughMullins catheter 26, and is positioned and deployed at or near the fossaovalis within the right atrium. A bridge stop 20 may be attached to thebridging element 12 and advanced with the septal member 30, oralternatively, the bridge stop 20 may be advanced to the right atriumside of the septal member 30 after the septal member has been positionedor deployed.

A fourth step can be generally described as adjusting the bridgingelement 12 for proper therapeutic effects. With the posterior bridgestop region 14, bridging element 12, and anterior bridge stop region 16configured as previously described, a tension is placed on the bridgingelement 12. The implant 10 and associated regions may be allowed tosettle for a predetermined amount of time, e.g., five or more seconds.The mitral valve and mitral valve regurgitation are observed for desiredtherapeutic effects. The tension on the bridging element 12 may beadjusted until a desired result is achieved. The bridge stop 20 is thenallowed to secure the bridging element 12 when the desired tension ormeasured length or degree of mitral regurgitation reduction is achieved.

III. Detailed Methods and Implantation Apparatus

The four generally described steps of implantation will now be describedin greater detail, including the various tools and apparatus used in theimplantation of the implant 10 or implant systems 22. An exemplaryembodiment will describe the methods and tools for implanting an implant10. These same or similar methods and tools may be used to implant animplant system 22 as well.

A. Establish Posterior Bridge Stop Region

1. Implantation Tools

Various tools may be used to establish the posterior bridge stop region14. For example, the great cardiac vein (GCV) catheter 40, the leftatrium (LA) catheter 60, and a cutting catheter 80 may be used.

FIG. 37A shows one embodiment of the GCV catheter 40 in accordance withthe present invention. The GCV catheter 40 preferably includes amagnetic or ferromagnetic head 42 positioned on the distal end of thecatheter shaft 45, and a hub 46 positioned on the proximal end. Thecatheter shaft 45 may include a first section 48 and a second section50. The first section 48 may be generally stiff to allow fortorquability of the shaft 45, and may be of a solid or braidedconstruction. The first section 48 includes a predetermined length,e.g., fifty centimeters, to allow positioning of the shaft 45 within thevasculature structure. The second section 50 may be generally flexibleto allow for steerability within the vasculature, i.e., into thecoronary sinus. The second section 50 may also include a predeterminedlength, e.g., ten centimeters. The inner diameter or lumen 52 of thecatheter shaft 45 is preferably sized to allow passage of a GCV guidewire 54, and additionally an LA guide wire 74 (see FIGS. 39 and 40).Both the GCV guide wire 54 and the LA guide wire 74 may be pre-bent, andboth may be steerable. The GCV catheter 40 preferably includes aradio-opaque marker 56 to facilitate adjusting the catheter under imageguidance to align with the LA catheter 60.

The magnetic or ferromagnetic head 42 is preferably polarized tomagnetically attract or couple the distal end of the LA catheter 60 (seeFIGS. 37B and 25). The head 42 includes a side hole 58 formed therein toallow for passage of the LA guide wire 74. As shown in FIG. 40, the leftatrial side 43 of the head 42 has an attracting magnetic force, and theexterior of the heart side 44 of the head 42 has a repelling magneticforce. It should be appreciated that these magnetic forces may bereversed, as long as the magnetic forces in each catheter coincide withproper magnetic attraction. The magnetic head 42 preferably includes abullet or coned shaped tip 55 to allow the catheter to track into thevasculature system. Within the tip 55 is an end hole 59, configured toallow for passage of the GCV guide wire 54.

FIG. 38 shows one embodiment of the LA catheter 60. Similar to the GCVcatheter 40, the LA catheter 60 preferably includes a magnetic orferromagnetic head 62 positioned on the distal end of the catheter shaft65 and a hub 66 positioned on the proximal end. The catheter shaft 65may include a first section 68 and a second section 70. The firstsection 68 may be generally stiff to allow for torquability of the shaft65, and may be of a solid or braided construction. The first section 68includes a predetermined length, e.g., ninety centimeters, to allowpositioning of the shaft 65 within the vasculature structure. The secondsection 70 may be generally flexible and anatomically shaped to allowfor steerability through the fossa ovalis and into the left atrium. Thesecond section 70 may also include a predetermined length, e.g., tencentimeters. The inner diameter or lumen 72 of the catheter shaft 65 ispreferably sized to allow passage of an LA guide wire 74, andadditionally may accept the guide wire 54 passed from the GCV. The LAcatheter 60 may include a radio-opaque marker 76 to facilitate adjustingthe catheter 60 under image guidance to align with the GCV catheter 40.

The magnetic or ferromagnetic head 62 of the LA catheter 60 is polarizedto magnetically attract or couple the distal end of the GCV catheter 40.As shown in FIG. 40, end side 64 of the head 62 is polarized to attractthe GCV catheter head 42. The magnetic forces in the head 62 may bereversed, as long as attracting magnetic poles in the LA catheter 60 andthe GCV catheter 40 are aligned. The magnetic head 62 preferablyincludes a generally planar tip 75, and also includes a center bore 78sized for passage of the cutting catheter 80 and the LA guide wire 74(see FIG. 38).

FIG. 41 shows the cutting catheter 80 preferably sized to be positionedwithin the inner diameter or lumen 72 of the LA catheter 60.Alternatively, the cutting catheter 80 may be positioned over the LAguide wire 74 with the LA catheter 60 removed.

The cutting catheter 80 preferably includes a hollow cutting tip 82positioned on the distal end of the catheter shaft 85, and a hub 86positioned on the proximal end. The catheter shaft 85 may include afirst section 88 and a second section 90. The first section 88 may begenerally stiff to allow for torquability of the shaft 85, and may be ofa solid or braided construction. The first section 88 includes apredetermined length, e.g., ninety centimeters, to allow positioning ofthe shaft 85 within the vasculature structure and the LA catheter. Thesecond section 90 may be generally flexible to allow for steerabilitythrough the fossa ovalis and into the left atrium. The second section 90may also include a predetermined length, e.g., twenty centimeters. Theinner diameter 92 of the catheter shaft 85 is preferably sized to allowpassage of the LA guide wire 74. The cutting catheter 80 preferablyincludes a radio-opaque marker 96 positioned on the shaft 85 so as tomark the depth of cut against the radio-opaque magnet head 62 or marker76 of the LA catheter 60.

The hollow cutting or penetrating tip 82 includes a sharpened distal end98 and is preferably sized to fit through the LA catheter 60 andmagnetic head 62 (see FIG. 42A). Alternatively, as seen in FIGS. 42B and42C, cutting or penetrating tips 100 and 105 may be used in place of, orin combination with, the hollow cutting tip 82. The tri-blade 100 ofFIG. 42B includes a sharp distal tip 101 and three cutting blades 102,although any number of blades may be used. The tri-blade 100 may be usedto avoid producing cored tissue, which may be a product of the hollowcutting tip 82. The elimination of cored tissue helps to reduce thepossibility of an embolic complication. The sharp tipped guide wire 105shown in FIG. 42C may also be used. The sharp tip 106 is positioned onthe end of a guide wire to pierce the wall of the left atrium and greatcardiac vein.

2. Implantation Methods

Access to the vascular system is commonly provided through the use ofintroducers known in the art. A 16F or less hemostasis introducer sheath(not shown), for example, may be first positioned in the superior venacava (SVC), providing access for the GCV catheter 40. Alternatively, theintroducer may be positioned in the subclavian vein. A second 16F orless introducer sheath (not shown) may then be positioned in the rightfemoral vein, providing access for the LA catheter 60. Access at boththe SVC and the right femoral vein, for example, also allows theimplantation methods to utilize a loop guide wire. For instance, in aprocedure to be described later, a loop guide wire is generated byadvancing the LA guide wire 74 through the vasculature until it exitsthe body and extends external the body at both the superior vena cavasheath and femoral sheath. The LA guide wire 74 may follow anintravascular path that extends at least from the superior vena cavasheath through the interatrial septum into the left atrium and from theleft atrium through atrial tissue and through a great cardiac vein tothe femoral sheath. The loop guide wire enables the physician to bothpush and pull devices into the vasculature during the implantationprocedure (see FIGS. 35A and 36A).

An optional step may include the positioning of a catheter or catheterswithin the vascular system to provide baseline measurements. An AcuNav™intracardiac echocardiography (ICE) catheter (not shown), or similardevice, may be positioned via the right femoral artery or vein toprovide measurements such as, by way of non-limiting examples, abaseline septal-lateral (S-L) separation distance measurement, atrialwall separation, and a mitral regurgitation measurement. Additionally,the ICE catheter may be used to evaluate aortic, tricuspid, andpulmonary valves, IVC, SVC, pulmonary veins, and left atrium access.

The GCV catheter is then deployed in the great cardiac vein adjacent aposterior annulus of the mitral valve. From the SVC, under imageguidance, the 0.035 inch GCV guide wire 54, for example, is advancedinto the coronary sinus and to the great cardiac vein. Optionally, aninjection of contrast with an angiographic catheter may be made into theleft main artery from the aorta and an image taken of the left coronarysystem to evaluate the position of vital coronary arterial structures.Additionally, an injection of contrast may be made to the great cardiacvein in order to provide an image and a measurement. If the greatcardiac vein is too small, the great cardiac vein may be dilated with a5 to 12 millimeter balloon, for example, to midway the posteriorleaflet. The GCV catheter 40 is then advanced over the GCV guide wire 54to a location in the great cardiac vein, for example near the center ofthe posterior leaflet or posterior mitral valve annulus (see FIG. 23).The desired position for the GCV catheter 40 may also be viewed asapproximately 2 to 6 centimeters from the anterior intraventricular veintakeoff. Once the GCV catheter 40 is positioned, an injection may bemade to confirm sufficient blood flow around the GCV catheter 40. Ifblood flow is low or non-existent, the GCV catheter 40 may be pulledback into the coronary sinus until needed.

The LA catheter 60 is then deployed in the left atrium. From the femoralvein, under image guidance, the 0.035 inch LA guide wire 74, forexample, is advanced into the right atrium. A 7F Mullins™ dilator with atrans-septal needle is deployed into the right atrium (not shown). Aninjection is made within the right atrium to locate the fossa ovalis onthe septal wall. The septal wall at the fossa ovalis is then puncturedwith the trans-septal needle and the guide wire 74 is advanced into theleft atrium. The trans-septal needle is then removed and the dilator isadvanced into the left atrium. An injection is made to confirm positionrelative to the left ventricle. The 7F Mullins system is removed andthen replaced with a 12F or other appropriately sized Mullins system 26.The 12F Mullins system 26 is positioned within the right atrium andextends a short distance into the left atrium.

As seen in FIG. 24, the LA catheter 60 is next advanced over the LAguide wire 74 and positioned within the left atrium. If the GCV catheter40 had been backed out to allow for blood flow, it is now advanced backinto position. The GCV catheter 40 is then grossly rotated tomagnetically align with the LA catheter 60. Referring now to FIG. 25,preferably under image guidance, the LA catheter 60 is advanced androtated if necessary until the magnetically attractant head 62 of the LAcatheter 60 magnetically attracts to the magnetically attractant head 42of the GCV catheter 40. The left atrial wall and the great cardiac veinvenous tissue separate the LA catheter 60 and the GCV catheter 40. Themagnetic attachment is preferably confirmed via imaging from severalviewing angles, if necessary.

Next, an access lumen 115 is created into the great cardiac vein (seeFIG. 26). The cutting catheter 80 is first placed over the LA guide wire74 inside of the LA catheter 60. The cutting catheter 80 and the LAguide wire 74 are advanced until resistance is felt against the wall ofthe left atrium. The LA guide wire 74 is slightly retracted, and while aforward pressure is applied to the cutting catheter 80, the cuttingcatheter 80 is rotated and/or pushed. Under image guidance, penetrationof the cutting catheter 80 into the great cardiac vein is confirmed. TheLA guide wire 74 is then advanced into the great cardiac vein andfurther into the GCV catheter 40 toward the coronary sinus, eventuallyexiting the body at the sheath in the neck. The LA catheter 60 and theGCV catheter 40 may now be removed. Both the LA guide wire 74 and theGCV guide wire 54 are now in position for the next step of establishingthe trans-septal bridging element 12.

B. Establish Trans-Septal Bridging Element

Now that the posterior bridge stop region 14 has been established, thetrans-septal bridging element 12 is positioned to extend from theposterior bridge stop region 14 in a posterior to anterior directionacross the left atrium and to the anterior bridge stop region 16.

In this exemplary embodiment of the methods of implantation, thetrans-septal bridging element 12 is implanted via a left atrium to GCVapproach. In this approach, the GCV guide wire 54 is not utilized andmay be removed. Alternatively, a GCV to left atrium approach is alsodescribed. In this approach, the GCV guide wire 54 is utilized. Thealternative GCV to left atrium approach for establishing thetrans-septal bridging element 12 will be described in detail in sectionIV.

The bridging element 12 may be composed of a suture material or sutureequivalent known in the art. Common examples may include, but are notlimited to, 1-0, 2-0, and 3-0 polyester suture, stainless steel braid(e.g., 0.022 inch diameter), and NiTi wire (e.g., 0.008 inch diameter).Alternatively, the bridging element 12 may be composed of biologicaltissue such as bovine, equine or porcine pericardium, or preservedmammalian tissue, preferably in a gluteraldehyde fixed condition.Alternatively the bridging element 12 may be encased by pericardium, orpolyester fabric or equivalent.

A bridge stop, such as a T-shaped bridge stop 120 is preferablyconnected to the predetermined length of the bridging element 12. Thebridging element 12 may be secured to the T-shaped bridge stop 120through the use of a bridge stop 150 (see FIG. 44A), or may be connectedto the T-shaped bridge stop 120 by securing means 121, such as tying,welding, or gluing, or any combination thereof. As seen in FIGS. 43A and43B, the T-shaped bridge stop 120 may be symmetrically shaped orasymmetrically shaped, may be curved or straight, and preferablyincludes a flexible tube 122 having a predetermined length, e.g., threeto eight centimeters, and an inner diameter 124 sized to allow at leasta guide wire to pass through. The tube 122 is preferably braided, butmay be solid as well, and may also be coated with a polymer material.Each end 126 of the tube 122 preferably includes a radio-opaque marker128 to aid in locating and positioning the T-shaped bridge stop 120. Thetube 122 also preferably includes atraumatic ends 130 to protect thevessel walls. The T-shaped bridge stop 120 may be flexurally curved orpreshaped so as to generally conform to the curved shape of the greatcardiac vein or interatrial septum and be less traumatic to surroundingtissue. The overall shape of the T-shaped bridge stop 120 may bepredetermined and based on a number of factors, including, but notlimited to the length of the bridge stop, the material composition ofthe bridge stop, and the loading to be applied to the bridge stop.

A reinforcing center tube 132 may also be included with the T-shapedbridge stop 120. The reinforcing tube 132 may be positioned over theflexible tube 122, as shown, or, alternatively, may be positioned withinthe flexible tube 122. The reinforcing tube 132 is preferably solid, butmay be braided as well, and may be shorter in length, e.g., onecentimeter, than the flexible tube 122. The reinforcing center tube 132adds stiffness to the T-shaped bridge stop 120 and aids in preventingegress of the T-shaped member 120 through the cored or pierced lumen 115in the great cardiac vein and left atrium wall.

Alternative T-shaped members or bridge locks and means for connectingthe bridging element 12 to the T-shaped bridge locks are described insection VI.

As can be seen in FIG. 27, the T-shaped bridge stop 120 (connected tothe leading end of the bridging element 12) is first positioned onto orover the LA guide wire 74. The deployment catheter 24 is then positionedonto the LA guide wire 74 (which remains in position and extends intothe great cardiac vein) and is used to push the T-shaped bridge stop 120through the Mullins catheter 26 and into the right atrium, and from theright atrium through the interatrial septum into the left atrium, andfrom the left atrium through atrial tissue into a region of the greatcardiac vein adjacent the posterior mitral valve annulus. The LA guidewire 74 is then withdrawn proximal to the tip of the deployment catheter24. The deployment catheter 24 and the guide wire 74 are then withdrawnjust to the left atrium wall. The T-shaped bridge stop 120 and theattached bridging element 12 remain within the great cardiac vein. Thelength of bridging element 12 extends from the posterior T-shaped bridgestop 120, through the left atrium, through the fossa ovalis, through thevasculature, and preferably the trailing end remains accessible exteriorthe body. Preferably under image guidance, the trailing end of thebridging element 12 is gently pulled, letting the T-shaped bridge stop120 separate from the deployment catheter 24. Once separation isconfirmed, again the bridging element 12 is gently pulled to positionthe T-shaped bridge stop 120 against the venous tissue within the regionof the great cardiac vein and centered over the great cardiac veinaccess lumen 115. The deployment catheter 24 and the guide wire 74 maythen be removed (see FIG. 28).

The trans-septal bridging element 12 is now in position and extends in aposterior to anterior direction from the posterior bridge stop region14, across the left atrium, and to the anterior bridge stop region 16.The bridging element 12 preferably extends through the vasculaturestructure and extends exterior the body.

C. Establish Anterior Bridge Stop Region

Now that the trans-septal bridging element 12 is in position, theanterior bridge stop region 16 is next to be established.

In one embodiment, the proximal portion or trailing end of the bridgingelement 12 extending exterior the body is then threaded through oraround an anterior bridge stop, such as the septal member 30.Preferably, the bridging element 12 is passed through the septal member30 outside of the body nearest its center so that, when later deployedover the fossa ovalis, the bridging element 12 transmits its force to acentral point on the septal member 30, thereby reducing twisting orrocking of the septal member. The septal member is advanced over thebridging element 12 in a collapsed configuration through the Mullinscatheter 26, and is positioned within the right atrium and deployed atthe fossa ovalis and in abutment with interatrial septum tissue. Thebridging element 12 may then be held in tension by way of a bridge stop20 (see FIGS. 29 and 30). The anterior bridge stop 20 may be attached toor positioned over the bridging element 12 and advanced with the septalmember 30, or alternatively, the bridge stop 20 may be advanced over thebridging element 12 to the right atrium side of the septal member 30after the septal member has been positioned or deployed. Alternatively,the bridge stop 20 may also be positioned over the LA guide wire 74 andpushed by the deployment catheter 24 into the right atrium. Once in theright atrium, the bridge stop 20 may then be attached to or positionedover the bridging element 12, and the LA guide wire 74 and deploymentcatheter 24 may then be completely removed from the body.

FIG. 44A is an exploded view of one embodiment of a bridge stop inaccordance with the present invention. The bridge stop 150 preferablyincludes a tube shaped base 152 and a screw 154. The base 152 includes afirst side 156 and a second side 158, wherein use, the first side 156 isdisposed toward the septal member 30, or optionally, the first side isdisposed over the septal member hub 31, and the second side 158 isadapted to receive the screw 154. The base 152 includes an axiallyconfigured bore 160 formed therein having threads 162 beginning at thesecond side 158 and extending partially within a length of the base 152,although the bore 160 may be threaded throughout its entire length. Thethreaded bore 160 includes a predetermined inner diameter 164, sized soas to allow the base 152 to be installed over a guide wire, andoptionally, positioned over the septal member hub 31. A first channel166 and, optionally, a second channel 168 may be included within thebore 160 extending from the first side 156 to partially within the base152 to provide for passage of the bridging element 12 within the bridgestop 150 (see FIG. 44B).

A male threaded portion 170 of screw 154 extends from the screw base 172to approximately midway the length of the screw 154 and is sized to bethreadably received within the bore 160 of the base 152. The screw head174 preferably includes torquing means such as parallel surfaces 176.Surfaces 176 are provided to allow the screw 154 to be tightened andloosened within the base 152. Screw 154 also includes a bore 178 formedtherein, sized so as to allow the screw 154 to be installed over a guidewire, and optionally, positioned over the septal member hub 31. A firstchannel 182 and, optionally, a second channel 184 may be included withinthe screw bore 178 extending partially within the screw 154, oralternatively, throughout the entire length of the screw 154 (see FIG.44C). The base 152 and the screw 154 are aligned such that the channelprovides for free passage of the bridging element 12 within the bridgestop 150.

In use, the screw 154 is first partially screwed into the base 152,allowing the channel 166, 168 in the base 152 to mate with the channel182, 184 in the screw 154. The bridging element 12 is then extendedthrough the entire length of the bridge stop 150, and is positionedwithin the channel formed within the base 152 and the screw 154. Thebridging element 12 is then tensioned and the screw 154 is torqued intothe base using a driver 186, such that the bridging element 12 isspooled within the bridge stop 150 or around the septal member hub 31,preferably one or more times. When the screw 154 is torqued into thebase all the way, the screw compresses against the bridging element 12,preventing any relative motion of the bridging element. The bridgingelement 12 can no longer move freely within the bridge stop 150, fixingthe position of the bridge stop 150 on the bridging element 12.

The driver 186 includes parallel surfaces 188, which are configured toextend over the screw head 174 in a mating relationship with parallelsurfaces 176 on the screw head 174. The driver 186 also includes a bore190 formed therein, sized so as to allow the driver 186 to be positionedover a guide wire.

The bridge stop 150, and alternative embodiments to be described later,have a predetermined size, e.g., eight millimeters by eight millimeters,allowing them to be positioned adjacent a septal member or a T-shapedmember, for example. The bridge locks are also preferably made ofstainless steel or other biocompatible metallic or polymer materialssuitable for implantation.

Additional alternative bridge stop embodiments are described in sectionV.

D. Bridging Element Adjustment

The anterior bridge stop 20 is preferably positioned in an abuttingrelationship to the septal member 30, or optionally may be positionedover the septal member hub 31. The bridge stop 20 serves to adjustablystop or hold the bridging element 12 in a tensioned state to achieveproper therapeutic effects.

With the posterior bridge stop region 14, bridging element 12, andanterior bridge stop region 16 configured as previously described, atension may be applied to the bridging element 12, either external tothe body at the proximal portion of the bridging element 12, orinternally, including within the vasculature structure and the heartstructure. After first putting tension on the bridging element 12, theimplant 10 and associated regions may be allowed to settle for apredetermined amount of time, e.g., five seconds. The mitral valve andits associated mitral valve regurgitation are then observed for desiredtherapeutic effects. The tension on the bridging element 12 may berepeatably adjusted following these steps until a desired result isachieved. The bridge stop 20 is then allowed to secure the desiredtension of the bridging element 12. The bridging element 12 may then becut or detached at a predetermined distance away from the bridge stop20, e.g., zero to three centimeters into the right atrium. The remaininglength of bridging element 12 may then be removed from the vasculaturestructure.

Alternatively, the bridging element 12 may be allowed to extend into theIVC and into the femoral vein, possibly extending all the way to thefemoral access point. Allowing the bridging element to extend into theIVC and into the femoral vein would allow for retrieval of the bridgingelement in the future, for example, if adjustment of the bridgingelement is necessary or desired.

The bridging element adjustment procedure as just described includingthe steps of placing a tension, waiting, observing, and readjusting ifnecessary is preferred over a procedure including adjusting while at thesame time—or real-time—observing and adjusting, such as where aphysician places a tension while at the same time observes a real-timeultrasound image and continues to adjust based on the real-timeultrasound image. The waiting step is beneficial because it allows forthe heart and the implant to go through a quiescent period. Thisquiescent period allows the heart and implant to settle down and allowsthe tension forces and devices in the posterior and anterior bridge stopregions to begin to reach an equilibrium state. The desired results arebetter maintained when the heart and implant are allowed to settle priorto securing the tension compared to when the mitral valve is viewed andtension adjusted real-time with no settle time provided before securingthe tension.

FIG. 31 shows an anatomical view of mitral valve dysfunction prior tothe implantation of the implant 10. As can be seen, the two leaflets arenot coapting, and as a result the undesirable back flow of blood fromthe left ventricle into the left atrium can occur. After the implant 10has been implanted as just described, the implant 10 serves to shortenthe minor axis of the annulus, thereby allowing the two leaflets tocoapt and reducing the undesirable mitral regurgitation (see FIGS. 32and 33). As can be seen, the implant 10 is positioned within the heart,including the bridging element 12 that spans the mitral valve annulus,the anterior bridge stop 20 and septal member 30 on or near the fossaovalis, and the posterior bridge stop 18 within the great cardiac vein.

IV. Alternative Implantation Steps

The steps of implantation as previously described may be altered due toany number of reasons, such as age, health, and physical size ofpatient, and desired therapeutic effects. In one alternative embodiment,the posterior T-shaped bridge stop 120 (or alternative embodiments) isimplanted via a GCV approach, instead of the left atrial approach aspreviously described. In an additional alternative embodiment, thecoring procedure of the left atrial wall is replaced with a piercingprocedure from the great cardiac vein to the left atrium.

A. GCV Approach

As previously described, penetration of the cutting catheter 80 into thegreat cardiac vein is confirmed under image guidance (see FIG. 26). Oncepenetration is confirmed, the LA guide wire 74 is advanced into thegreat cardiac vein and into the GCV catheter 40. The LA guide wire 74 isfurther advanced through the GCV catheter 40 until its end exits thebody (preferably at the superior vena cava sheath). The LA catheter 60and the GCV catheter 40 may now be removed. Both the LA guide wire 74and the GCV guide wire 54 are now in position for the next step ofestablishing the trans-septal bridging element 12 (see FIG. 35A). Atthis point, an optional exchange catheter 28 may be advanced over the LAguide wire 74, starting at either end of the guide wire 74 and enteringthe body at either the femoral sheath or superior vena cava sheath, andadvancing the exchange catheter 28 until it exits the body at the otherend of the guide wire 74. The purpose of this exchange catheter is tofacilitate passage of the LA guidewire 74 and bridging element 12, in aprocedure to be described below, without cutting or injuring thevascular and heart tissues. In a preferred embodiment, the exchangecatheter 28 is about 0.040 to 0.060 inch ID, about 0.070 to 0.090 inchOD, about 150 cm in length, has a lubricious ID surface, and has anatraumatic soft tip on at least one end so that it can be advancedthrough the vasculature without injuring tissues. It is to beappreciated that the ID, OD, and length may vary depending on thespecific procedure to be performed.

In the GCV approach, the trans-septal bridging element 12 is implantedvia a GCV to left atrium approach. A predetermined length, e.g., twometers, of bridging element 12 (having a leading end and a trailing end)is connected at the leading end to the tip of the LA guide wire 74 thathad previously exited the body at the superior vena cava sheath and thefemoral sheath. In this embodiment, the LA guide wire 74 serves as theloop guide wire, allowing the bridging element to be gently pulled orretracted into and through at least a portion of the vasculaturestructure and into a heart chamber. The vascular path of the bridgingelement may extend from the superior vena cava sheath through thecoronary sinus into a region of the great cardiac vein adjacent theposterior mitral valve annulus, and from the great cardiac vein throughatrial tissue into the left atrium, and from the left atrium into theright atrium through the interatrial septum, and from the right atriumto the femoral sheath.

As can be seen in FIGS. 34A to 34D, a crimp tube or connector 800 may beused to connect the bridging element 12 to at least one end of the LAguide wire 74. FIG. 34A shows a crimp tube 800 preferably having anouter protective shell 802 and an inner tube 804. The outer protectiveshell 802 is preferably made of a polymeric material to provideatraumatic softness to the crimp tube, although other crimpablematerials may be used. The inner tube 804 may be made of a ductile ormalleable material such as a soft metal so as to allow a crimp to holdthe bridging element 12 and guide wire 74 in place. The crimp tube ends806 may be gently curved inward to aid in the movement of the crimp tubeas the tube 800 moves through the vasculature. It is to be appreciatedthat the crimp tube may simply comprise a single tube made of a ductileor malleable material.

The bridging element 12 is positioned partially within the crimp tube800. A force is applied with a pliers or similar crimping tool to createa first crimp 808 (see FIG. 34B). The end of the bridging element mayinclude a knot, such as a single overhand knot, to aid in the retentionof the bridging element 12 within the crimp tube. Next, the LA guidewire 74 is positioned partially within the crimp tube 800 opposite thebridging element 12. A force is again applied with a pliers or similarcrimping tool to create a second crimp 810 (see FIG. 34C).Alternatively, both the bridging element 12 and the guide wire 74 may beplaced within the crimp tube 800 at opposite ends and a single crimp 812may be used to secure both the bridging element 12 and the guide wire 74within the crimp tube (see FIG. 34D). It is to be appreciated that thecrimp tube 800 may be attached to the bridging element 12 or guide wireprior to the implantation procedure so as to eliminate the step ofcrimping the bridging element 12 within the crimp tube 800 during theimplantation procedure. The guide wire 74 is now ready to be gentlyretracted. It can also be appreciated that apparatus that uses adhesivesor alternatively pre-attached mechanisms that snap together may also beused for connecting bridge elements to guidewires.

As can be seen in FIG. 35B, the LA guide wire 74 is gently retracted,causing the bridging element 12 to follow through the vasculaturestructure. If the optional exchange catheter 28 is used (as shown inFIGS. 35 A and 35B), the LA guidewire 74 retracts through the lumen ofthe exchange catheter 28 without injuring tissues. The LA guide wire 74is completely removed from the body at the femoral vein sheath, leavingthe bridging element 12 extending from exterior the body (preferably atthe femoral sheath), through the vasculature structure, and againexiting at the superior vena cava sheath. The LA guide wire 74 may thenbe removed from the bridging element 12 by cutting or detaching thebridging element 12 at or near the crimp tube 800.

A posterior bridge stop, such as a T-shaped bridge stop 120 ispreferably connected to the trailing end of bridging element 12extending from the superior vena cava sheath. The T-shaped bridge stop120 is then positioned onto or over the GCV guide wire 54. A deploymentcatheter 24 is then positioned onto or over the GCV guide wire 54 and isused to advance or push the T-shaped bridge stop 120 and bridgingelement 12 through the right atrium, through the coronary sinus, andinto the great cardiac vein. If the optional exchange catheter 28 isused, the exchange catheter is gently retracted with the bridgingelement 12 or slightly ahead of it (see FIGS. 36A and 36B). Optionally,the bridging element 12 may be pulled from the femoral vein region,either individually, or in combination with the deployment catheter 24,to advance the T-shaped bridge stop 120 and bridging element 12 intoposition in the great cardiac vein. The GCV guide wire 54 is thenretracted letting the T-shaped bridge stop 120 separate from the GCVguide wire 54 and deployment catheter 24. Preferably under imageguidance, and once separation is confirmed, the bridging element 12 isgently pulled to position the T-shaped bridge stop 120 in abutmentagainst the venous tissue within the great cardiac vein and centeredover the GCV access lumen 115. The deployment catheter 24 and optionalexchange catheter 28 may then be removed.

The T-shaped bridge stop 120 and the attached bridging element 12 remainwithin the great cardiac vein. The length of bridging element 12 extendsfrom the posterior T-shaped bridge stop 120, through the left atrium,through the fossa ovalis, through the vasculature, and preferablyremains accessible exterior the body. The bridging element 12 is nowready for the next step of establishing the anterior bridge stop region16, as previously described, and as shown in FIGS. 28 to 30.

B. Piercing Procedure

In this alternative embodiment, the procedure to core a lumen from theleft atrium into the great cardiac vein is replaced with a procedurewhere a sharp-tipped guide wire within the great cardiac vein is used tocreate a passage from the great cardiac vein into the left atrium.Alternative embodiments for the magnetic head of both the GCV catheter40 and the LA catheter 60 are preferably used for this procedure.

FIGS. 45A and 45B show an end to side polarity embodiment for the GCVcatheter magnetic head 200 and the LA catheter magnetic head 210.Alternatively, a side to side polarity may be used. The GCV cathetermagnetic head 200 can maintain the same configuration for both the endto side polarity and the end to end polarity, while the LA cathetermagnetic head 215 is shown essentially rotated ninety degrees for theside to side polarity embodiment (see FIG. 46).

As seen in FIG. 45B, the GCV catheter magnetic head 200 includes a duallumen configuration. A navigation guide wire lumen 202 allows the GCVguide wire 54 to extend through the cone or bullet shaped end 204 of thehead 200 in order to steer the GCV catheter 40 into position. A secondradially curved side hole lumen 206 allows the sharp tipped guide wire105 (or tri-blade 100, for example) to extend through the head 200 anddirects the sharp tipped guide wire 105 into the LA catheter magnetichead 210. The LA catheter magnetic head 210 includes a funneled end 212and a guide wire lumen 214 (see FIG. 45C). The funneled end 212 directsthe sharp tipped guide wire 105 into the lumen 214 and into the LAcatheter shaft 65.

FIG. 46 shows the alternative embodiment of the LA catheter magnetichead 215 used with the side to side polarity embodiment. The head 215may have the same configuration as the GCV catheter magnetic head 42shown in FIGS. 39 and 40 and described in section III. The head 215includes a navigation guide wire lumen 216 at the cone or bullet shapedend 218, and a side hole 220. The side hole 220 funnels the sharp tippedguide wire 105 (or tri-blade 100, for example), from the GCV catheter 40to the LA catheter 60 and directs the guide wire 105 into the LAcatheter shaft 65.

In use, both the GCV catheter 40 and the LA catheter 60 are advancedinto the great cardiac vein and left atrium as previously described. TheGCV catheter 40 and the LA catheter 60 each includes the alternativemagnetically attractant head portions as just described. As best seen inFIGS. 45A and 45B, a sharp-tipped guide wire 105 is advanced through theGCV catheter 40 to the internal wall of the great cardiac vein. Thesharp-tipped guide wire 105 is further advanced until it punctures orpierces the wall of the great cardiac vein and the left atrium, andenters the funneled end 212 within the LA catheter head 210. Thesharp-tipped guide wire 105 is advanced further until it exits theproximal end of the LA catheter 60. Both the GCV catheter 40 and the LAcatheter 60 may now be removed, leaving the GCV guide wire 54 and thesharp-tipped guide wire 105 in place. The posterior T-shaped bridge stop120 is now implanted via the GCV approach, as previously described, andas shown in FIGS. 35A to 36B.

V. Alternative Bridge Stop Embodiments

Additional alternative embodiments of bridge stop devices may be usedand are herein described. The bridge stop serves to secure the bridgingelement 12 at the posterior or anterior bridge stop region 14, 16, orboth.

FIGS. 47A and 47B are perspective views of an alternative embodiment ofa bridge stop 300 in accordance with the present invention. The bridgestop 300 preferably includes a fixed upper body 302 and a movable lowerbody 304. Alternatively, the upper body 302 may be movable and the lowerbody 304 may be fixed. The upper body 302 and lower body 304 arepositioned circumjacent a tubular shaped rivet 306. The upper body 302and lower body 304 are preferably held in position by the rivet head 308and a base plate 310. The rivet 306 and base plate 310 includes apredetermined inner diameter 312, sized so as to allow the bridge stop300 to be installed over a guide wire. A spring, such as a spring washer314, or also known in the mechanical art as a Belleville Spring, ispositioned circumjacent the rivet 306 and between the rivet head 308 andthe upper body 302, and applies an upward force on the lower body 304.The lower body 304 is movable between a bridge unlocked position (seeFIG. 47A), and a bridge locked position (see FIG. 47B). In the bridgeunlocked position, the lower body 304 and the upper body 302 are not incontacting communication, creating a groove 320 between the upper body302 and lower body 304. In the bridge locked position, the axial forceof the spring washer 314 urges the lower body 304 into contacting, ornear contacting communication with the upper body 302, whereby thebridging element 12, which has been positioned within the groove 320, islocked in place by the axial force of the lower body 304 being appliedto the upper body 302.

In use, the bridging element 12 is positioned within the groove 320while the lower body 304 is maintained in the bridge unlocked position316. The bridge stop 300 is positioned against the septal member 30 andthe bridging element 12 is adjusted to proper tension. The lower body304 is then allowed to move toward the upper body 302, thereby fixingthe position of the bridge stop 300 on the bridging element 12.

FIGS. 48A and 48B are perspective views of an alternative embodiment ofthe bridge stop 350 shown in FIGS. 47A and 47B. The bridge stop 400preferably includes an extension or tension spring 402 wherein at leastone revolution of the spring coils 404 is in a contacting relationshipwhile the spring 402 is in a natural or no-load position. When in atensioned state, the at least one revolution of the spring coils 404 isin a non-contacting relationship. In use, an axial tension force isapplied to the spring 402, allowing the spring coils 404 to separate(see FIG. 48A). While in the tensioned state, the bridging element 12 ispositioned between and/or around at least one, and preferably multiplespring coils 404. The bridge stop 400 is positioned against the septalmember 30 and the bridging element 12 is adjusted to proper tension. Thetension force is then removed from the spring 402 and the spring 404 isallowed to return to its no-load state (see FIG. 48B). In the spring'sno-load state, the coils 404 provide a tight fit against the bridgingelement 12, thereby fixing the position of the bridge stop 400 on thebridging element 12.

FIG. 49 is a cross sectional view of an alternative embodiment of abridge stop 450 in accordance with the present invention. The bridgestop 450 preferably includes a plunger 452 within a tube 454. The tube454 includes a plunger bore 456 extending partially through the lengthof the tube 454. The bore 456 then tapers inward at 460 creating asmaller bore 462. An internally threaded portion 466 of plunger bore 456extends from the first side 468 of the tube 454 to approximately midwaybetween the first side 468 and the second side 470 of tube 454.Alternatively, the threaded portion 466 may be external on the tube 454.The plunger 452 is positioned within the plunger bore 456. The plunger452 has a conical shaped head 472 and a shaft 474 extending from thebase 476 of the conical shaped head 472. A torque screw 478, having afirst side 480 and a second side 482, is threaded into bore 456. Thefirst side 480 includes receiver means for a driver tool to rotate thetorque screw 478, such as, but not limited to phillips, slotted, sixlobe, or square. The second side 482 includes a pocket 484. Acompression spring 486 having a first end 488 is positioned within thepocket 484, and a second end 490 of the compression spring 486 ispositioned over the shaft 474 of the plunger 452.

An aperture 492 is disposed within the wall of the shaft 474 at a pointabove where the plunger bore 456 begins to taper inward. Bridgingelement 12 is shown disposed through the small bore 462 and throughaperture 492.

In use, the torque screw 478 may be backed off to allow the plunger head472 to move away from the tapered portion 460 of the plunger bore 456.Bridging element 12 is disposed within bore 462 and extends out of thetube 454 at aperture 492. The bridge stop 450 is then positioned againstthe septal member 30 and the bridging element 12 is adjusted to propertension. The torque screw 478 is then torqued into the bore 456, causingthe plunger head 472 to provide a tight fit against the bridging element12, thereby fixing the position of the bridge stop 450 on the bridgingelement 12.

FIG. 50 is a cross sectional view of an additional alternativeembodiment of a bridge stop 550 in accordance with the presentinvention. The bridge stop 550 preferably includes a base portion 552having a first side 554 and a second side 556, a cap 558 threaded overthe base portion 552, and a collet 560 positioned between the secondside 556 of the base 552 and the cap 558. The collet 560 is seated onthe second side 556 of the base 552. A bore 562 extends axially throughthe base 552, collet 560, and cap 558. In use, the cap 558 may be backedoff to allow the bore 562 within the collet 560 to expand sufficientlyto allow the bridging element 12 to slide freely through the bridge stop550. The bridge stop 550 is then positioned against the septal member 30and the bridging element 12 is adjusted to proper tension. The cap 558is then tightened onto the base 552, which causes the bore 562 withinthe collet 560 to close down. The collet 560 provides a tight fitagainst the bridging element 12, thereby fixing the position of thebridge stop 550 on the bridging element 12. Collet 560 can be made of anelastomer or deformable type of material to make the pinching force moredistributed and less traumatic to the bridging element 12.

FIG. 51 is a perspective view of an additional alternative embodiment ofa bridge stop 650 in accordance with the present invention. The bridgestop 650 comprises a housing 652 having a lid 654. The bridge stop 650may be tubular in shape, and may include an axially positioned lumen 656extending therethru; the lumen 656 being sized to allow the bridge stop650 to be positioned over a guide wire for implantation and optionallysecured to hub 31 of the septal member 30. A second radially offsetaxial lumen 658 also extends through the bridge stop 650. The secondlumen 658 allows for passage of the bridging element 12 through thebridge stop 650.

Positioned within the housing 652 is a spring band 660 and a spacer 662.The spring band 660 is generally circular in shape and has a fixed end664 and a free end 666. The fixed end 664 includes a tab 668 positionedwithin a slot 670 in the lid 654 to prevent movement of the fixed end.The free end 666 includes an inclined angle 672 which allows forcircumferential displacement when the inclined angle 672 is depressed.The spacer 662 is positioned adjacent the spring band 660, and keeps thespring band in alignment and free of buckling. As seen in FIG. 51, ascrew 674 may be positioned in the lid 654, and when turned into thebridge stop 650, the screw 674 provides a force on the inclined angle672. The free end 666 of the spring band 660 is caused to rotate towardthe fixed end 664, thereby pinching the bridging element 12 within thebridge stop 650 (between the fixed end 664 and the free end 666), andfixing the position of the bridge stop 650 on the bridging element 12.

It is to be appreciated that each embodiment of the bridge stop may beconfigured to have a bridge securing configuration in its static state,so as to require a positive actuation force necessary to allow thebridging element to move freely within or around the bridge stop. When adesirable tension in the bridge element is achieved, the actuation forceis removed, thereby returning the bridge stop back to its static stateand securing the bridge stop to the bridging element. Alternatively, thebridge stop may be configured to allow free movement of the bridgingelement 12 in its static state, thereby requiring a positive securingforce to be maintained on the bridge stop necessary to secure thebridging element within the bridge stop.

Preferably, the bridge securing feature is unambiguous via tactile orfluoroscopic feedback. The securing function preferably may be lockedand unlocked several times, thereby allowing the bridging element to bereadjusted. The bridge stop material is also desirably radio-opaque orincorporates radio-opaque features to enable the bridge stop to belocated with fluoroscopy.

VI. Alternative T-Shaped Bridge Stop Embodiments

Additional alternative embodiments of T-shaped bridge stop devices maybe used and are herein described. The T-shaped bridge stop may serve tosecure the bridging element 12 at the anterior bridge stop region 16, orthe posterior bridge stop region 14, or both. It is to be appreciatedthat the alternative embodiments of the T-shaped bridge stop devices maybe symmetrical as shown, or may also be asymmetrically shaped.

FIG. 52A is a perspective view of an alternative embodiment of aT-shaped bridge stop 700 in accordance with the present invention. TheT-shaped bridge stop 700 preferably includes an intravascular stent 702and, optionally, a reinforcing strut 704. The stent 702 may be a balloonexpandable or self expanding stent. As previously described, theT-shaped bridge stop 700 is preferably connected to a predeterminedlength of the bridging element 12. The bridging element 12 may be heldwithin, on, or around the T-shaped bridge stop 700 through the use ofany of the bridge locks as previously described, or may be connected tothe T-shaped bridge stop 700 by way of tying, welding, or gluing, forexample, or any combination.

FIG. 52B is a perspective view of an alternative embodiment of theT-shaped bridge stop 700 in accordance with the present invention. Thealternative T-shaped bridge stop 701 preferably includes a lattice orhalf round intravascular stent 703 and, optionally, a reinforcing strut704. The “C” shaped stent 703 may be a balloon expandable stent or selfexpanding stent. As previously described, the T-shaped bridge stop 701is preferably connected to a predetermined length of the bridgingelement 12. The bridging element 12 may be held within, on, or aroundthe T-shaped bridge stop 701 through the use of any of the bridge locksas previously described, or may be connected to the T-shaped bridge stop701 by way of tying, welding, or gluing, for example, or anycombination.

FIGS. 53A to 53E show alternative methods of connecting the bridgingelement 12 to a T-shaped bridge stop 710. FIG. 53A shows a T-shapedmember 710 where the bridging element 12 is wound around the T-shapedmember 710. The bridging element 12 may be secured by adhesive 712,knot, or a securing band placed over the bridging element 12, forexample. Alternatively, the bridging element 12 may first be threadedthrough a lumen 714 extending through the T-shaped member 710perpendicular the length of the T-shaped member. The bridging element 12may then be wound around the T-shaped member, and secured by adhesive712, securing band, or knot, for example.

FIG. 53B shows a T-shaped member 710 where the bridging element 12 iswelded or forged to a plate 716. The plate 716 may then be embeddedwithin the T-shaped member 710, or alternatively, secured to theT-shaped member 710 by gluing or welding, for example.

FIGS. 53C and 53D show alternative embodiments where a ball and socketjoint 718 connects the bridging element 12 to the T-shaped member 710.In FIG. 53C, the ball and socket joint 718 is located external to theT-shaped member 710. Alternatively, the ball and socket joint 718 may bepositioned partially or completely within the T-shaped member 710, asseen in FIG. 53D. The bridging element 12 is secured to the socket 720,and the ball 722 is secured to the T-shaped member 710. The ball andsocket joint 718 allows for free rotation of the bridging element 12relative to the T-shaped member 710 or vice versa. The ball and socketjoint 718 is preferably made of a micro-machined stainless steel,although other implantable materials may be used as well.

FIG. 53E shows an additional alternative embodiment of the T-shapedmember 710 where the bridging element 12 is embedded in a polymericsubstrate 724 of the T-shaped member 710. In this embodiment, thebridging element 12 preferably is a braided stainless steel micro-cable.The end 726 of the bridging element 12 is separated into an assortmentof strands 728, which are then embedded in the polymeric substrate 724.

FIG. 53F shows a guide wire or bridging element style hinged T-shapedbridge stop embodiment 730 having a hinged leg 732. When in the expandedstate, as shown in FIG. 53F, the hinged leg 732 forms one arm of a “T.”The hinged leg 732 has a “C” shaped or concave profile, allowing thehinged leg 732 to lie over the guide wire or bridging element 12 whiletracking to its final location. When the guide wire or bridging element12 is gently retracted, the hinged leg 732 pivots away from the bridgingelement 12 forming the T-shaped bridge stop.

VII. Alternative Anterior Bridge Stop Embodiments

In place of, or in combination with the septal member 30 previouslydescribed, alternative embodiments of an anterior bridge stop may beused.

FIG. 54 shows an implant 10 having a T-shaped bridge stop 710 in thegreat cardiac vein and an anterior T-shaped bridge stop 750. Theanterior T-shaped bridge stop 750 may be of a construction of any of theT-shaped bridge stop embodiments described. The T-shaped member 750includes a lumen 752 extending through the T-shaped member 750perpendicular to the length of the T-shaped member. The bridging element12 may be secured by a free floating bridge stop as previouslydescribed.

FIG. 55 shows an implant 10 having a T-shaped bridge stop 710 in thegreat cardiac vein and an anterior lattice style bridge stop 760. Thelattice 762 is positioned on the septal wall at or near the fossaovalis. Optionally, the lattice 762 may include a reinforcement strut764 to distribute the bridging element 12 tension forces over a greaterarea on the septal wall. The anterior lattice style bridge stop 760 maybe packed in a deployment catheter with the bridging element 12 passingthrough its center. The lattice 762 is preferably self expanding and maybe deployed by a plunger. The bridging element 12 may be secured by afree floating bridge stop as previously described.

FIG. 56A shows an implant 10 having a T-shaped bridge stop 710 in thegreat cardiac vein and an anterior star shaped bridge stop 770. The star772 is positioned on the septal wall at or near the fossa ovalis. Thestar shaped bridge stop 770 may be packed in a deployment catheter withthe bridging element 12 passing through its center. The star 772 ispreferably self expanding and may be deployed by a plunger. When thestar shaped bridge stop 770 is deployed, the center portion 774 standsproud of the septal wall to concentrate forces to the star points 776(see FIG. 56B). The bridging element 12 may be secured by a freefloating bridge stop as previously described.

FIG. 57 shows an additional embodiment of an anterior bridge stop 820.The bridge stop 820 includes at least two arms 822 extending radiallyfrom a generally central portion 824, and preferably includes more thantwo arms, as shown in FIG. 57. The bridge stop 820 is positioned on theseptal wall at or near the fossa ovalis. The bridge stop 820 may bepacked in a deployment catheter with the bridging element 12 passingthrough its center lumen 826. The bridge stop is preferably selfexpanding and may be deployed by a plunger after being folded into acatheter. The bridging element 12 may be secured by a free floatingbridge stop as previously described or fixed in position.

FIG. 58 shows an additional embodiment of an anterior bridge stop 830.The bridge stop 830 again includes at least two arms 832, and preferablyincludes more than two. In this embodiment, each arm 832 is anindependent member, and is free to move relative to the remaining arms.The bridge stop 830 is positioned on the septal wall at or near thefossa ovalis. The bridge stop 830 may be packed in a deployment catheterwith the bridging element 12 passing through a lumen 836 in each arm;the lumen being located generally central along the longitudinal axis ofeach arm. The bridge stop is preferably self expanding and may bedeployed by a plunger. The bridging element 12 may be secured by a freefloating bridge stop as previously described or fixed in position.

FIG. 59 shows an additional embodiment of an anterior bridge stop 840.The bridge stop 840 includes at least one main trunk 842, and at leastone arm 844 extending radially from the trunk 842, and preferably morethan one arm, as shown in FIG. 59. The bridge stop 840 is positioned onthe septal wall at or near the fossa ovalis. The bridge stop 840 may bepacked in a deployment catheter with the bridging element 12 passingthrough a lumen 846; the lumen being located generally central along thelongitudinal axis of the trunk 842. The bridge stop is preferably selfexpanding and may be deployed by a plunger. The bridging element 12 maybe secured by a free floating bridge stop as previously described orfixed in position.

FIG. 60A shows an additional embodiment of an anterior bridge stop 850.The bridge stop 850 includes at least one arm 852 extending radiallyfrom a generally central portion 854, and preferably includes more thanone arm, as shown in FIG. 60A. The bridge stop 850 is positioned on theseptal wall at or near the fossa ovalis. The bridge stop 850 may bepacked in a deployment catheter 24 with the bridging element 12 passingthrough its center lumen 856 (see FIG. 60B). The bridge stop 850 may beself expanding and may be deployed by a plunger, or alternatively may bedeployed by applying tension on a deployment wire 858 and pushing on theplunger to expand the at least one arm 852. The forces of the deploymentwire 858 and plunger cause the bridge stop 850 to be plasticallydeformed into its final shape. The bridging element 12 may be secured bya free floating bridge stop as previously described or fixed inposition.

FIGS. 61A to 62B show additional embodiments of an anterior bridge stopincorporating the use of porcine or equine pericardium to spread thetension forces of the bridging element 12, and also to provide a paddingsurface to the septal wall and to promote the bridge stop's ingrowthwithin the septal wall tissue.

As can be seen in FIG. 61A, a pad 862 of pericardium is positioned onthe septal wall side of a bridge stop 860. The bridge stop 860 as shownincludes a plurality of arms 864 extending radially from a generallycentral portion 866. The bridge stop 860, including the pericardium pad862, is positioned on the septal wall at or near the fossa ovalis, withthe pericardium pad 862 positioned between the septal wall and thebridge stop 860. The bridge stop 860 and pericardium pad 862 may bepacked in a deployment catheter 24 with the bridging element 12 passingthrough both the bridge stop 860 and the pericardium pad 862 (see FIG.61B). The bridge stop 860, including the pericardium pad 862, ispreferably self expanding and may be deployed by a plunger. The bridgingelement 12 may be secured by a free floating bridge stop as previouslydescribed or fixed in position.

FIG. 62A shows an alternative embodiment of the bridge stop 860. FIG.62A shows a bridge stop 870 positioned between at least two layers ofpericardium 872. Pericardium 872 may be a single piece of pericardiumhaving a butterfly cut to allow the bridge stop 870 to be positionedbetween the two layers, or the pericardium may include at least twoseparate pads, so as to allow the bridge stop 870 to be positionedbetween the at least two pads. The bridge stop 870 as shown includes aplurality of arms 874 extending radially from a generally centralportion 876. The bridge stop 870, including the pericardium pad 872, ispositioned on the septal wall at or near the fossa ovalis, with onelayer of the pericardium pad 872 being positioned between the septalwall and the bridge stop 870, and the other layer of pericardium 872exposed to the right atrium. The bridge stop 870 and pericardium pad 872may be packed in a deployment catheter 24 with the bridging element 12passing through both the bridge stop 870 and the pericardium pad 872(see FIG. 62B). The bridge stop 870, including the pericardium pad 872,is preferably self expanding and may be deployed by a plunger. Thebridging element 12 may be secured by a free floating bridge stop aspreviously described or fixed in position.

Both bridge stop embodiments 860 and 870 may include any of theself-expanding embodiments described herein, and as shown arenon-limiting embodiments for incorporation with a pericardium pad orpads. It should also be appreciated that pads 862 and 872 may becomposed of biological tissue other than pericardium and further may belined with polyester fabric or equivalent to promote tissue in-growth.

FIGS. 63A to 63C show an additional embodiment of an inflatable anteriorbridge stop 880. The bridge stop 880 includes a balloon portion 882 anda central portion 884. The balloon portion 882 may take on any number ofshapes, and is shown as a loop or ring. The central portion 884 maycomprise a fabric or other implantable material to allow for tissueingrowth. The balloon 882 may be inflated with a glue material in aliquid state, such as an epoxy glue, or other materials that will hardenallowing the balloon to maintain its expanded configuration. Theresulting pressure from the inflation process encourages the balloonportion 882 and the central portion 884 to expand to its deployedconfiguration. When the balloon inflation material has hardened, thehoop or ring shaped balloon spreads the tension force from the bridgingelement 12 and keeps the central fabric portion open and flat. Thebridge stop 880 is positioned on the septal wall at or near the fossaovalis. The bridge stop 880 may be packed in a deployment catheter 24with the bridging element 12 passing through a lumen 886 in the centralportion 884 (see FIG. 63B). The bridge stop is preferably self expandingand may be deployed by a plunger. FIG. 63C shows the bridge stop 880just after exiting the deployment catheter 24 and prior to inflation ofthe balloon portion 882. The bridging element 12 may be secured by afree floating bridge stop as previously described or fixed in position.

VIII. Fixed Length Bridging Element for Predetermined Tension Across aHeart Valve Annulus or for Predetermined Reduction in Septal-LateralLength

In order to achieve desired septal-lateral mitral valve dimension, theproper bridge length between the fossa ovalis and the GCV must beselected.

The septal-lateral mitral valve annulus length and the fossa ovalis toGCV length may be readily assessed using three dimensionalechocardiography or magnetic resonance imaging, for example, eitherprior to or during the implantation procedure in order to properly sizethe fixed length bridging element prior to implantation.

FIGS. 64 to 66 show embodiments of an implant system 910 having a fixedlength bridging element. Implantation of the implant 910 having a fixedlength bridging element is similar to the implantation of the implant 10and adjustable bridging element 12 as previously described, except thatthe bridging element is of a fixed length and is not adjusted during orafter implantation. The overall length of the fixed length bridgingelement may be chosen as a percentage, e.g., 125 to 150 percent, of thedesired septal-lateral length. The length of the fixed length bridgingelement will always be greater than the desired septal-lateral length.

Normal septal-lateral distances measured in normal persons may be usedas a basis for determining the proper therapeutic septal-lateraldistances in persons being treated. Target therapeutic septal-lateraldistance may, for example, be chosen as some percentage, e.g. 125percent, of septal-lateral distance in normal persons. The targetseptal-lateral distance must be sufficient to produce a therapeuticreduction in mitral regurgitation, but not over-stretch or tear tissues.

The use of a fixed length bridging element may reduce the complexity ofthe implantation of the implant system 910 because adjustment of abridging element is not required. The implant system may also reduce theoverall length of time for the implantation procedure.

The fixed length bridging element may be generally straight, as shown inFIG. 67, or may be generally arched or non-linear, as shown in FIGS. 68and 69. FIGS. 65 and 66 show a sample of alternative deviations of thepath of the arched fixed length bridging element 932, similar to thoseshown in FIGS. 12 to 20. Any single deviation or combinations of lateralor medial deviations and/or superior or inferior deviations in this pathcan be imparted, if desired, to affect the nature and direction of theforce vector or vectors that the implant 910 applies. It should beappreciated that the fixed length bridging element can be preformed orotherwise configured with various medial/lateral and/orinferior/superior deviations to achieve targeted annulus and/or atrialstructure remodeling, which takes into account the particulartherapeutic needs and morphology of the patient. In addition, deviationsin the path of the fixed length bridging element may also be imparted inorder to avoid the high velocity blood path within a heart chamber, suchas the left atrium. Also, stainless steel and Nitinol bridge elementsmay be used (as previously described and represented by FIGS. 13 to 17and 19) that have curved septal to lateral components that impartdesired ranges of tension and length in combination.

A. Fixed Length Bridging Element Structure

The fixed length bridging element may be constructed of a generallyrigid material, such as stainless steel, in order to provide apredetermined reduction in the septal-lateral length, while allowing awider range of tension across the heart valve annulus. Alternatively,the fixed length bridging element may be constructed of a semi-flexibleor springy material, such as Nitinol, in order to provide apredetermined narrow range of tension across a heart valve annulus, suchas the mitral valve annulus. A semi-flexible or springy material alsofacilitates the implantation of the fixed length bridging element usinga deployment catheter. Nitinol has favorable fatigue properties and isalso non-thrombogenic.

As shown in FIG. 67, the fixed length bridging element 912 comprises ahollow tube 920 having a connective or retentive member or head 922 at afirst end and a retainer or stop 924 at a second end. The inner diameterof the hollow tube 920 must be large enough to enclose bridging element12. The head 922 is preferably cone or chevron shaped and may include atleast one crevice or slit 926 sized to allow each portion of the head922 to flex so that the head can be inserted into a receiving aperture123 in a T-shaped member or bridge stop 120 and snap into place (seeFIGS. 70A and 70B). The stop 924 at the second end of the hollow tube920 may be any practical shape (i.e. circular, square, triangle, or rodshaped) that offers sufficient surface area to abut the septal member 30without allowing the stop 924 of the fixed length bridging element 912to pass through the septal member. Alternatively, a septal member 30 maynot be used and the stop 924 may abut the septal wall. Stop 924, forexample, may incorporate any of the bridge stop embodiments describedherein, and more particularly may incorporate any of the embodimentsdescribed in FIGS. 54 to 63C.

As previously described in relation to the implant 10, the stop 924 andthe bridge stop 120 remain free to move back and forth independent ofthe inter-atrial septum and the inner wall of the great cardiac veinduring a portion of the cardiac cycle when the tension force may bereduced or becomes zero (see FIGS. 71A and 71B).

FIGS. 68 and 69 show an alternative embodiment of a fixed lengthbridging element. The arched fixed length bridging element 932 comprisesa hollow tube 940 having a connective or retentive head 942 at a firstend and a retainer or stop 944 at a second end. The head 942 ispreferably cone or chevron shaped and may include at least one creviceor slit 946 sized to allow each portion of the head 942 to flex so thatthe head can be inserted into a receiving aperture 123 in a T-shapedmember or bridge stop 120 and snap into place (see FIGS. 70A and 70B).The stop 944 at the second end of the hollow tube 940 may be anypractical shape (i.e. circular, square, triangle, or rod shaped) thatoffers sufficient surface area to abut the septal member 30 withoutallowing the stop 944 of the fixed length bridging element 932 to passthrough the septal member 30. Alternatively, a septal member 30 may notbe used and the stop 944 may abut the septal wall. Stop 944, forexample, may incorporate any of the bridge stop embodiments describedherein, and more particularly may incorporate any of the embodimentsdescribed in FIGS. 54 to 63C.

As previously described in relation to the implant 10, the stop 944 andthe bridge stop 120 remain free to move back and forth independent ofthe inter-atrial septum and the inner wall of the great cardiac veinduring a portion of the cardiac cycle when the tension force may bereduced or becomes zero (see FIGS. 71A and 71B).

B. Detailed Methods for Fixed Length Bridging Element Implantation

The steps of implantation and implantation apparatus as described insections III(A) “Establish Posterior Bridge Stop Region” and III(B)“Establish Trans-Septal Bridging Element” are also used in conjunctionwith the implantation of the fixed length bridging element 912 and 932and are therefore not repeated here. The remaining steps forimplantation of the fixed length bridging element are described below.In addition, the bridging element 12 as described in these steps takeson an alternative purpose of serving as a “tracking rail” for deliveryof the fixed length bridging element to its final implanted position.

1. Establish Anterior Bridge Stop Region

Now that the trans-septal bridging element or tracking rail 12 is inposition, the anterior bridge stop region 16 is next to be established.In an alternative embodiment not incorporating a septal member 30, thestep including the deployment of the septal member 30 may be skipped.

As seen in FIG. 29, the LA guide wire 74 is first backed out to at leastthe right atrium. In one embodiment incorporating a septal member 30,the proximal portion of the tracking rail 12 extending exterior the bodyis then threaded through or around the septal member 30. Preferably, thetracking rail 12 is passed through the septal member 30 outside of thebody nearest its center so that when the fixed length bridging element912 later passes over the tracking rail 12, the stop 924 of the fixedlength bridging element 912 will also be centered and will transmit itsforce to a central point on the septal member 30, thereby reducingtwisting or rocking of the septal member. The septal member is advancedover the tracking rail 12, through the vasculature, and is positionedwithin the right atrium and deployed at the fossa ovalis in a mannerconsistent with the manufacturer's instructions. At this point, tensionmay be applied under image guidance to establish the appropriate tensionand/or length of bridging needed.

2. Fixed Length Bridging Element Positioning

With the posterior bridge stop region 14, tracking rail 12, and anteriorbridge stop region 16 configured as described, the fixed length bridgingelement 912, 932 is next to be positioned. External the body, the fixedlength bridging element 912, 932 is positioned over the tracking rail 12having an end remaining external the body. With a tension maintained onthe tracking rail 12, the deployment catheter 24 may then be used togently push the fixed length bridging element 912, 932 through thevasculature and into the right atrium, following the path of thetracking rail 12. When a septal member 30 is used, additional pushing ofthe deployment catheter 24 allows the shaped head of the fixed lengthbridging element 912, 932 to pass through the interstices of the septalmember 30 until the stop 924, 944 of the fixed length bridging elementcomes to rest on the septal member 30 and restricts further passage (seeFIG. 72). When a septal member 30 is not used, the stop 924, 944 comesto rest on the septal wall and restricts further passage. FIG. 73 showsthe deployment of the arched fixed length bridging element 932 withoutthe use of a septal member, and prior to the deployment of the stop 944.

Still with continued tension maintained on the tracking rail 12, acompressive force is applied to the deployment catheter 24 causing theshaped head 922, 942 to continue to follow the path of the tracking rail12 directly into the receiving aperture 123 in the T-shaped member 120.The shaped head 922, 942 snaps into place within the aperture 123 in theT-shaped member (see FIGS. 70A and 70B). The tracking rail 12 may thenbe cut or detached, leaving a portion free to dangle or recoil withinthe tube 920, 940 of the fixed length bridging element, with theremainder removed along with the deployment catheter 24.

Alternatively, the tracking rail 12 may be allowed to extend into theIVC and into the femoral vein, possibly extending all the way to thefemoral access point. Allowing the tracking rail to extend into the IVCand into the femoral vein would allow for future retrieval of thetracking rail, which would provide for access to the fixed lengthimplant.

The foregoing is considered as illustrative only of the principles ofthe invention. Furthermore, since numerous modifications and changeswill readily occur to those skilled in the art, it is not desired tolimit the invention to the exact construction and operation shown anddescribed. While the preferred embodiment has been described, thedetails may be changed without departing from the invention, which isdefined by the claims.

We claim:
 1. A system for treating a human or animal heart, the systemcomprising: an implant sized and configured for placement partiallywithin a left atrium, said implant comprising a bridging element, ananterior bridge stop, and a posterior bridge stop, said posterior bridgestop in the form of an elongate structure, a guide wire of sufficientlength and sufficiently small diameter for deployment in anintravascular path that has a length that is greater than a length froma first vascular access site into the heart chamber and from the heartchamber to a second vascular access site different than the firstvascular access site, and a connector to connect an end of the implantto one end of the guide wire with sufficient gripping strength to enablean operator to pull the implant along at least a portion of theintravascular path into the heart chamber.
 2. A system according toclaim 1 wherein the bridging element comprises a metallic material orpolymer material or a metallic wire form structure or a polymer wireform structure or suture material or equine pericardium or porcinepericardium or bovine pericardium or preserved mammalian tissue.
 3. Thesystem of claim 1 wherein the elongate structure forms a T-shapedstructure with said bridging element.
 4. The system of claim 1 whereinthe elongate structure is a stent.
 5. The system of claim 1 wherein theelongate structure is curved.
 6. The system of claim 5 wherein thecurvature of the elongate structure generally conforms to a curvature ofan inside of a typical human Great Cardiac Vein.
 7. A system fortreating a human or animal heart, the system comprising: an implantsized and configured for placement partially within a heart chamber,said implant comprising a bridging element, an anterior bridge stop, anda posterior bridge stop; a guide wire; a connector to connect an end ofthe implant to one end of the guide wire with sufficient grippingstrength to enable an operator to pull the implant along at least aportion of an intravascular path into the heart chamber; a firstcatheter having a first lumen therethrough and a first distal endregion, said first distal end region having a first magnetic head, saidfirst magnetic head comprising a permanent magnet having a lumen atleast partially therethrough and a first orifice therein through theside wall of said first magnetic head, said first orifice of sufficientdiameter for said guidewire to pass therethrough and said lumen in thefirst magnetic head in communication with the lumen in said firstcatheter; and a second catheter having a second lumen therethrough and asecond distal end region, said second distal end region having a secondmagnetic head, said second magnetic head comprising a permanent magnethaving a lumen therein, said lumen in said second magnetic head incommunication with the lumen in said second catheter, said first andsecond magnetic heads of sufficient strength and of orientation ofpolarity when brought in proximity to each other they align said firstand second orifice so that the guide wire may pass through one orificeinto the other.
 8. A system according to claim 7 wherein the strengthand polarity of said first magnetic head and said second magnetic headare sufficient to align and temporarily hold said first and said secondorifice while separated by a width of human tissue.
 9. A systemaccording to claim 8 wherein the width of tissue is the width of tissuebetween the interior of the left atrium and the interior of the greatcardiac vein.
 10. A system according to claim 7 wherein the lumen of thesecond catheter is open at an end of the second catheter and the orificein the second magnetic head is located on a terminus of the secondcatheter and surrounds, in whole or in part, the lumen of the secondcatheter such that when said first magnetic head and said secondmagnetic head are magnetically attached, the magnetic heads aregenerally perpendicular.
 11. A system according to claim 7 said firstmagnetic head is located at a tip of said first catheter.
 12. A systemaccording to claim 7 wherein said first orifice in the first magnetichead communicates with a ramp between said first orifice and the lumenin the first magnetic head.
 13. An implant according to claim 7 whereinsaid posterior bridge stop is an elongate member and forms a T shapedstructure with said bridging element.
 14. An implant according to claim13 wherein said elongate member is curved.
 15. An implant according toclaim 14 wherein said elongate member has a curvature that approximatesa curvature of an inside of a typical human Great Cardiac Vein.
 16. Animplant according to claim 7 wherein said posterior bridge stop is astent.